Basch was born in 1929 in Tacovo, modern day Tachiv, in the Carpathian Mountains which were then the most easterly part of Czechoslovakia. In 1941 there were 2,150 Jews living in Tacovo.
Basch’s parents were Mendel and Blanka. She had two siblings, her twin Ignac (b. 1929) and her younger sister Ruzena (b. 1930). It is unknown if these were her only siblings.
There is little information about Basch’s childhood other than that she was part of an ultra-orthodox family.