Rabbi Hillel Poisic (15.1.1881 Zlatopol, Ukraine – 1953 Tel Aviv, Israel) was a communal worker and Torah scholar. He was an expert in releasing agunot from their husbands, who abandoned them without divorce.
The Poisic (also Poisik, Posek, Possek) family is a rabbinical family originated in the Shapira family and connected to it in marriage relationships. The Poisic members were active in Ukraine.
Rabbi Hillel Poisic's father, Rabbi Elijah Poisic (1859-1932), was one of the most important Rabbis in Ukraine. He served as rabbi in Mohlika and in Zlatopol and composed Responsa and halakhic books about Sukkot, Maimonides and the letter of divorce (get). His expertise was in circumcision law. His mother, Matalia, daughter of Zwi Sonik, was the granddaughter of Rabbi Chaim Chaikel Shapira from Kalininblatt (in Kiev district), father of Rabbi Judah Josef Loeb Shapira, president of the rabbinical court in Rakhmistrivka, and R. Israel Volodarsky, president of court in Petrikovka (in Kherson district). Rabbi Hillel studied Torah with his father and grandfather, Rabbi Moshe Zvi Poisic. He received his ordination as rabbi by the most important rabbis in south Russia, Rabbi Moshe Nathan Rubinstein from Vinnitsa and the Rabbi Yosef Halperin, president of the court of the Jewish community in Odessa.
In 1898 Rabbi Hillel Poisic was married to Gitel (Tovah), the daughter of his uncle R. Selig Shapira. In 1899-1921 R. Hillel served as rabbi in Zlatopol and was elected by both the Jewish community and the Ukrainian authorities as a religious rabbi and a formal rabbi. When the pogroms began in Ukraine (in 1920) and the different gangs of robbers oppressed him much and threw him to the jail for several times, he decided to move to Romania. In 1921 he escaped together with his family from the revolt, pogroms and religions suppression in Russia. He went through many tribulations of travel till he arrived in 1921 to Bessarabia (east Moldova), which belonged to Romania that time. He served one year as rabbi in Markulshty and later on in Tatarbunary, Bessarabia (Akkerman district, Romania-Bessarabia). He was received there as a "Romanian citizen" and as a formal rabbi. He was also a Jewish religions teacher in the governmental high schools. There he began again to be engaged in communal work; he founded charity institutions and distributed the Torah amongst the poor.