In 1838 Warringal Village was subdivided into nine portions (ranging in size from one to two square miles), with one of the largest portions, number 5, being purchased in 1840 by settler James Watson. He named the land Rose Anna Farm, after his wife Elizabeth Anna Rose. However, in April 1843 Watson encountered financial difficulties, was charged with fraud and was successfully sued. His company became insolvent and he was subsequently forced to subdivide and sell lots of the farm. Up until the early 1890s, four-fifths of the farm remained as an intact estate. However, in 1901 the Hurstbridge railway line was extended from Heidelberg to run to Rosanna, and in 1902 was further extended through to Eltham.  This led to further subdivision and sale of lots.^[3][4][5]

The Rosanna Post Office opened on 12 March 1914, closed in 1917 and reopened in 1926.^[6]

^Wikipedia