Königsberg, 22 January 1945. Attestation of Ingeborg Schiweck
The official evacuation of Königsberg was ordered on 27 January 1945. By that time, the Soviet winter offensive into East Prussia was two weeks old, and Red Army troops started to near the city. A wave of refugees from the eastern parts of the province fled ahead of the advancing Soviet troops, causing great anxiety in the city. Anticipating its encirclement, on 21 January East Prussia's Gauleiter Erich Koch ordered the evacuation of his employees, and this news travelled fast. Many people started to make preparations to leave the city, and Ingeborg Schiweck, a student at the Ostpreussische Mädchengewerbeschule, managed to get an official attestation, stating that "as of today [and] for the time being [she] is given time off from classes"

Königsberg, 8 February 1944. Deutsches Rotes Kreus Personalausweis of Hertha Prinzen
This German Red Cross Passport was given out to Hertha Prinzen on 8 February 1944. Apparently, it was time to renew her documents, as the stamps on the left page indicate that her passport would be valid for one more month. It is renewed until March 1945, which suggests that she was in Königsberg during the city's siege.

Königsberg, 1 February, 1943. German Red Cross Membership card Hertha Prinzen
This membership card, a document that also belong to Hertha Prinzen, is signed by the office of Königsberg's mayor, Dr. Helmuth Will, and stamped by the Deutsches Rotes Kreuz Kreisstelle Königsberg (Pr)-Stadt. 
The name Will is clearly readable. Dr. Will would eventually head a Volkssturm battalion, and surrendered on 9 April 1945. He returned from his time as a prisoner of war in 1955.

Königsberg, 19 November 1942. Work card of Iwan Maksemenko
Millions of people from the Soviet Union were brought to Germany as forced labourers. Forced labour drives were a double-edged sword: on one hand Soviet men, women, and children replaced the German men who had to serve in the military, on the other this was a means to rob the Soviet Union of its labour potential. Given East Prussia's location in the far east of the Reich, it was often the first contact with Germany these people had, These forced labourers could be exchanged in case they did not perform adaquately, and in this regard they were treated little different than other "goods".
This boy, Iwan Maksemenko, was only 15 years old by the time he was taken from the Zhytomyr area and brought to Königsberg, where he worked in the Staditsches Fuhrpark (part of  the public trasport). 
For someone like Maksemenko, the two most likely plights in 1945 were equally bleak. Germans (especially  the militay) saw in the Soviet labour force a potential threat, and thousands were killed in the final stage of the war. East Prussia was no exception in this regard. The other option was that, once he was liberated by the Red Army, Maksemenko would be screened and deemed a traitor who had supported the German war economy. This ensured that he would likely spend the post-war years in the Gulag camps. 

Pillau, 1944. Cuff title "Marinelazarett Pillau/Ostpr."
Between 1938 and February 1945 there was a Marinelazarett (Navy hospital) in Pillau. After the Navy hospital in Memel was dissolved in November 1944, Pillau was the only remaining Navy hospital in East Prussia. In March 1945, the nearest Navy hospital, in Gotenhafen (Gdynia), was resignated as Festungslazarett (Fortress hospital), marking the end of the Navy hospitals in the area.
Little is known about this cuff title, but it is likely to be of similar nature to the better-known yellow cufftitles reading "Deutsche Wehrmacht", which clarified that the (civilian) wearer in question performed auxiliary functions for the military.
Pillau would become the main port from where East Prussian refugees fled westwards. Whether they were evacuated by ship, or crosssed over the Frische Nehrung, Pillau was often a stop on the way.

Königsberg, 31 January 1945. Marching orders, or Marschbefehl, of Dr. Otto Beyer
Some military and civilian bodies and their personnel were given the opportunity to leave Königsberg around the time of the city's encirclement on 28 January 1945. This was normally because their services were considered to be more useful elsewhere. 
Dr. Otto Beyer, who throughout the war had served as head of East Prussia's economic department for Wholesale and Foreign Trade, received permission to leave Königsberg, This permission was granted by the president of the Gau Chamber of Commerce, the Gauwirtschaftkammer, in consultation with the Reich Defence Commissar, the Reichsverteidigungskommissar, Gauleiter Erich Koch.

Königsberg, 5 February 1945. Registration for food supply of Willy Teichmann at NSDAP Ortsgruppe Ziethen
Red Army troops managed to encircle Königsberg on 29 January, which marked the beginning of a siege that would last until 9 April. Königsberg was the capital of East Prussia, and was considered a safe haven for those refugees coming from the east of the province, prompting many to flee towards it. Many of Königsberg's inhabitants, meanwhile, had fled the city in anticipation of its siege. As a result, by early February there were roughly 200,000 people in the city: 150,000 refugees and 50,000 original inhabitants.

This registration for food supply gives some idea how the regime organised the care for the population during the siege. As during the earlier years, people  had to report to the local Ortsgruppe in order to be eligible to receive foodstuffs. Recipients of ration cards (in this case Willy Teichmann) also had to leave an address (Krausallee 5). This also meant, however, that tasks could be expected from them and authorities knew where to find them. In the second week of February the fortress commander General Otto Lasch, in consultation with the highest-ranking Party official in the city, Kreisleiter Ernst Wagner, proclaimed "Fortress Service", which forced everyone in Königsberg, man, woman, and child, to contribute to its defence for four hours per day. Tying this service to the distribution of food was a way to ensure that people would comply to this order.

East Prussia, October 1944 - April 1945. Wehrpass Julius Bednarz
East Prussia was not an isolated or unique battle field, it was part of a long war. The soldiers fighting there were not merely fighting for their homeland, they were also fighting because, simply put, they were soldiers. The Wehrpass of Julius Bednarz (his picture is on its first page, shown on the inset left) shows that most soldiers had a long war behind them by the time they fell back on German soil. Bednarz, who was born in 1899, was initially not part of the fighting units, but deployed on the home front (1939) and as part of the occupation forces in Poland (1940). In July 1941 he is part of the Campaign against Russia in the rear, returns to the home front for a few months, and in January 1942 joins the Campaign against Russia again. In the spring of 1942 he defends the area near Cholm, and from then on takes part in the defensive fighting of Army Group North. In late August 1944 he is honorably discharged, but already six weeks later, on 13 October 1944, he is called up again to take part in the defence of East Prussia. His Wehrpass, together with about 100 others, was found during excavations in Kaliningrad in 2016. 

Heiligenbeil pocket (near Guttstadt), 11 February 1945. Trauerbericht of Leutnant Werner Göttling
In National Socialist rhetoric, dying for Germany was one of the highest honours a man could achieve, which is clearly shown in this letter to the father of Leutnant Werner Göttling, written by the commander of his unit, Hauptmann Ledi. The stilted nature of the writing reveals a certain dogmatic standard that can be found in most of these letters. "Our comrade fell on German soil, and his unit is likewise showing its commitment (...) I therefore ask you to live by the example your son set for his men: his commitment sanctifies our cause, and his death for our heavily struggling Fatherland is not in vain, so long as he, like the hundreds of thousands of dead before us, is not forgotten." 

Heiligenbeil Kessel, 13 February 1945. Letter of Obergefreiter Alfred Heller.
German soldiers sent 30 to 40 billion Feldpost letters during the Second World War, and this letter was sent via Königsberg's Lgpa (Luftgaupostamt) by Alfred Heller, an Obergefreiter at the 1. Battr. schw. Flak. 251, which was part of the 18. Flakdivision that was deployed in the Heiligenbeil Kessel. It reads:
Im Osten, am 13.2.45 

Meine lieben Eltern u. Lisa! 

Am heutigen Tage will ich euch wieder ein paar Zeilen  schreiben in der Hoffnung, daß sie Euch bei bester  Gesundheit antreffen. Bin immer munter und guter Dinge und habe mein Leben ganz in die Hände unseres  Herrgotts gelegt und habe vollstes Vertrauen, daß er mich beschützen wird. Seid auch Ihr stark und verliert die Hoffnung auf ein glückliches Wiedersehen nicht. „In Gottes Namen“ steht es schon in meinem Feldgesangbuch. Daß meine Gedanken immer bei Euch sind brauche ich wohl kaum zu sagen. Im Vertrauen auf Gott und ein gütiges Geschick schließe ich für heute und verbleibe wie immer mit herzlichen Grüßen.

Euer Alfred
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In the East, 13 February 1945,
Dear parents and Lisa!
Today I want to write you a few lines again in the hope that they will reach you in good health. I am always cheerful and in good spirits and have put my life completely in the hands of our Lord God and have every confidence that he will protect me. Please be strong as well and do not lose hope for a happy reunion. "In the name of God" is already written in my military hymnal. I hardly need to say that my thoughts are always with you. I end today, trusting in God and good fortune, and remain as always with warm regards.

Your Alfred

Königsberg, late March/ early April 1945. Pamplet aimed at Volkssturm men
Pamplets like these were used on both the Eastern and Western Front to encourage soldiers to surrender. Often, these are generic messages, but in some cases, like these, they had a specific target audience. In this case, it is aimed at the Volkssturm militia units in Königsberg. These were inferior units, consisting of old men and young boys. In Königsberg these two age groups were separated, with the old men serving mostly in the south, and given that this pamplets appeals to the readers' senses, it is probably aimed at an older readership. 

Near Königsberg, 12 April 1945, Pamphlet "General der Infanterie Otto LASCH. An den Oberbefehlshaber der 4. Armee Herrn General der Infanterie MUELLER"
General Otto Lasch was the Fortress commander of Königsberg and General Friedrich-Wilhelm Müller, the commander of the Fourth Army, was his direct superior. Lasch and Müller did not have the best of relationships, and in his memoirs Lasch distanced himself from Müller, who was extradited to Greece and sentenced to death for war crimes. Only days before Lasch "wrote" this pamphlet, on 8 April 1945, Lasch received a telegram from Müller, which stressed that Lasch’s officers’ honour bound him to hold Königsberg to the last bullet. We don't know how Lasch reacted to this telegram, but at the time Lasch had already ordered a breakout, which is discussed in some detail in this pamphlet.
The pamphlet, ostensibly between the two commanders but meant for wide distribution among all men under Müller's command on the Samland peninsula, also gives a matter-of-fact description of the fighting in Königsberg. It talks about the chaos among the civilian population and the poor communication with Party officials.
It concludes as follows: "You know, Herr General, that conditions on the Samland are similar to those in Königsberg and that the even more numerous civilian population has no way of escaping the combat zone." This clearly betrays "Red Army editing", as during the previous months neither Lasch nor Müller had bothered much for the civilians in their areas of operation, and Lasch would know that this argument would not sway Müller in any meaningful way. 

Samland peninsula, East Prussia, 13 April 1945, Pamphlet "An die deutschen Offiziere und Soldaten!"
Immediately after Königsberg's surrender its high-ranking officers and generals were interrogated. They were also coerced into signing a pamphlet to the German officers and soldiers that were still holding out on the west of the Samland. The Red Army started its attack on this grouping on 13 April, and would capture Pillau by the end of the month. To encourage German troops to surrender, this pamphlets stated that despite the fact that Königsberg had a 100.000-man garrison it was "forced to lay down our arms because further resistance was completely pointless."
Among the signees, we find Königsberg's fortress commander and his chief of staff, General Otto Lasch and Oberst Hugo von Süsskind-Schwendi; three divisional commanders: Generalleutnant Hermann Haenle (367th Infanterie-Division), Generalmajor Kaspar Fölker (69th Infanterie-Division - still identified by his previous rank "Oberst"), and Generalleutnant Hans Mikosch (Division z. b. V. Mikosch ); and five further Oberste.

Moravia (Mähren), 14 April 1945, Pamphlet of the Nationalkomitee Freies Deutschland
Königsberg fell on the night of 9-10 April 1945 as one of the final German holdouts. The Soviet-backed "National Committee Free Germany" quickly spread this information to other German troops to demoralise them. This pamphlet presents vastly inflated numbers of P.O.W.s (the real number of German soldiers in Königsberg stood at around 55,000 as the siege commenced), while also the number of 42,000 deaths was completely fictitious, as by the time this pamphlet was printed no effort had been made to make an accurate count of the victims of the fighting.  
It is unclear why this pamphlet is aimed at the 8th Panzer-Division and 17th Panzer-Division. None of these units hailed from East Prussia, and they were not defending a similar fortified position. 

Moscow/ Königsberg, 10 April 1945, Congratulatory pamplets of the capture of Festung Königsberg.
On the left:
Order No. 333 of the Supreme Commander Marshal of the Soviet Union Comrade Stalin of 9 April 1945, expresses gratitude to all those who took part in the battles, including you, for defeating the Königsberg group of German troops and mastering the fortress and the main city of East Prussia - Königsberg.
==============
On the right:
To the participant of the fighting in Königsberg, Comrade Smesik
Order No. 333 of the Supreme Commander Marshal of the Soviet Union Comrade Stalin of 9 April 1945, expresses gratitude to our army, and therefore you, the participant of the battle for the fortress and the main city of East Prussia, Königsberg, for the excellent fighting. 
The military council congratulates you and expresses a firm belief that you will smash and destroy our sworn enemies even stronger. Go west! Let’s hoist the banner of victory over Berlin!
Army Military Council

Soviet Union, 1946 and 1948. Certificates for the award of the medal "For the capture of Königsberg"
The medal "For the capture of Königsberg" was established on June 9, 1945 by decree of the Presidium of the Supreme Soviet of the USSR, simultaneous with the medals for the capture of Budapest, Vienna, and Berlin, and awarded to "all direct participants in the heroic assault and capture of Budapest, Königsberg, Vienna and Berlin, as well as the organizers and leaders of military operations during the capture of these cities."
"The medal is presented on behalf of the Presidium of the Supreme Soviet of the USSR on the basis of documents certifying actual participation in the storming and taking of these cities, issued by the unit commanders and commanders of military medical institutions."
Depending on the time and minting, medals could difffer slightly, while, as we see here, also the size of the cerificates could be different. By 1987, about 760,000 people were awarded with the medal.