Nissan Nico was born in 1907 in Dyneburg (Dvinsk), Latvia, to an observant family. He was sent to study in yeshiva and was found to be sharp, talented and well-versed in Jewish sources. His teachers said he was destined to be a great rabbi. However, in 1924, at age seventeen, he attended a lecture by Ze’ev Jabotinsky in Riga and was deeply impressed. This proved to be a turning point in his life, as he joined the Beitar movement, becoming one of its activists and investing most of his time and energy in it. Ultimately, he became a commander and went to be trained at a farm. He then assumed command of the Beitar cell in Riga.
In 1933, Nissan joined a group of Beitar members to make aliyah as Mapilim. In 1935, he joined the Tel Aviv Police. When he joined Etzel, he transmitted information he had come upon as a policeman: what the Arabs were doing and that they were planning to riot against their Jewish neighbors. He reported to them that the CID was planning to arrest and search Jewish suspects. This involved great personal peril.
When Etzel split in 1940, he followed Yair and joined Lehi. In 1942, he was arrested by the British on suspicion of being a Lehi member. For two years, he was held in Latrun. He developed a gastrointestinal condition. Due to the poor medical care in the camp, his condition grew worse. The Arab doctors not only failed to relieve his pain; they actually caused him damage. His comrades say this was done on purpose. He was transferred to the government-owned hospital, where his leg had to be amputated. Since his condition did not improve, he was transferred to HaYarkon Hospital on Tel Aviv. There he passed away on 10.5.1944. Few attended his funeral, due to their concerns of being arrested. He was buried in Nahalat Yitzhak Cemetery in Tel Aviv.
Nissan was beloved by all of his friends. In the worst moments, he maintained his cheerful spirit. He would joke with his friends and thus inspire and uplift them.
In 1984, he received the commendation for prisoners of the British Mandate given out by the Ministry of Defense of the State of Israel — the State he never lived to see established.