Leah Miron Katzenelson was born January 15 1888 in Bobruisk, Russia to Avraham and Tzipora Meron. She came from an affluent family. She was joined the Poalei Zion party. An active Zionist she associated with like minded Zionist. These included Sarah Schmuckler, Rachel Katzenelson (wife of Zalman Shazar), Batya Brenner (sister of Yosef Chaim Brenner) and Batya Shein (wife of Eliezer Shein ) and of course Berl Katzenelson. At 16 she participated with Schmuckler in a discussions concerning the problems of the Jewish people and socialism, which Berl conducted in their hometown. Her friendship with Berl developed into love but when her father found him in their home forbade her to meet him anymore.
A few months after Berl left for Israel in 1909 she followed him as part of the Second Aliyah. She joined Berls Kinneret in 1914. Joining the group at the Sea of Galilee as one of the five girls in the ‘Group of Friends’. Four of whom were from the city of Bobruisk: Meron, Schmuckler, Shane, Katzenelson and Brenner. The ‘Bobruisk Group’ led the vegetable garden work on the farm. Her relationship with Berl and Sarah Schmuckler was difficult. When Sarah moved to treat patients at Yesod HaMa’ala, she kept in touch with her. In May 1919 she rushed to the hospital in Safed to be with her and held her in her arms when Sarah died.
After the death of Sarah Schmuckler in 1919, the relationship between Leah and Berl became stronger again and they lived as a couple. Leah split her life between Kinneret and Jaffa until she decided to leave the farm and tried to settle in Ein Harod. Later moving to Tel Aviv. During this period the Histadrut Labor Federation was founded. In 1921 she participated in the first conference of workers in Israel held in Balfouria.
The couple never married, but in 1921 Berl issued her a Histadrut membership card, stating that she was married to him. During the period of her life with Berl (1920–1944), Leah accepted the importance of Berl’s role as a labor leader. At the end of his life when he was ill, Leah attended to him on his sickbed. Out of understanding for his love for Sarah, Leah agreed that Berl would be buried next to her.
After Berl’s death in 1944 she was among the activists for the preservation of Berl’s legacy as a member of the board of the foundation for the establishment of a seminary for youth counsellors and activists which was named after Berl Katzenelson. She continued to live in their apartment on Maza’a Street. She bequeathed the house and its contents to the labor movement.
In 1959 she moved to Ein Harod Ihud with her sister Bluma (wife of Eliezer Moshe Slutskin).
She died in 1967 at the hospital in Afula and was buried in the Kinneret Group’s cemetery near Berl’s grave.