Complex sentence: During most of latter part of the First World War, Bārda was a refugee in Russia, and after returning to Latvia in 1918 he died in 1919 of a kidney disease he had been suffering from since his time in Vienna.
Split into simpler sentences: During most of latter part of the First World War, Bārda was a refugee in Russia. He returned to Latvia in 1918, but died in 1919 of a kidney disease he had been suffering from since his time in Vienna.