Given name: Josef Family name: Kapłan

Grew up in a religious family, a student of a heder and a yeshiva, and then of a Polish school where Hebrew was the language of instruction. Since he was 13 years old he belonged to Haszomer Hacair, with time became the activist of the organisation in Warsaw. On the turn of 1940 he organised the underground activity of Haszomer Hacair in eastern Poland. Since 1940 he was in the Warsaw ghetto. Worked in the Joint office, set up Maapilim kibbutz. Was sent to Czestochowa where he helped set up a kibbutz in Zarki. Informed foreign Jewish organisations about the situation of the Jewis community in occupied Poland. Passed information to the Histadrut headquaters in Switzerland. In 1941 he finished his book which documented the Haszomer Hacair activity. It was published in 1942 in Palestine. His flat at Nowolipki Street No. 25, which he occupied with Miriam Heinsdorf, was an important contact place for the organisation (Kaplan fabricated documents for the underground activists there). He was also the co-founder of the first combat detachment in the ghetto. Acted in the Jewisn National Committee, was elected a member of the Jewish Fighting Organisation staff. On 3 September 1942 was arrested by the Gestapo in Landau's shop where he worked. Most probably one of the member of the resistance movement, who had been arrested a couple days earlier, denounced him. Kaplan was killed in Pawiak prison on 11 September 1942.