Casani was born Joseph Zisling in
Baranowitz, near
Minsk in
Belarus, then in the
Russian Empire, He had one sister and four brothers, one of whom,
Aharon, eventually became a highly influential figure among the founders of the state of
Israel, serving as its first
Minister of Agriculture under the provisionally formed government. In 1908 or 1909, Joseph was sent to the
Transvaal Colony (modern-day
South Africa) to work for an uncle, Bernard Cartoon, who owned a wine and spirits store in
Krugersdorp. In 1912, he enrolled in the South West Rhodesia volunteers, apparently using the name of Joseph Goldman. In 1914, he enlisted in General Botha's Army but was discharged due to ill health in 1915. After brief service in the South African Army, he made his way to England and enlisted in the British Army, at first as Joe Goldman. He changed this to John Goldman and then joined the RAF in 1917 under the name John Golman. ==Military service in World War I==