 In 1887 he left the Regular Army and became a second lieutenant in the Royal East Kent Yeomanry, serving until 1890.In 1885, Walsh entered Parliament as Conservative MP for Radnorshire and held the seat until his defeat by Liberal Francis Edwards in 1892.On 26 July 1890, he had married Lady Clementine Pratt, the only daughter of the 3rd Marquess Camden.