Which men held the position of prime minister on 3 occasions?

Alfred Deakin. He succeeded Sir Edmund Barton as Australia's second Prime Minister, serving from September 1903 until April 1904. He served his second term from July 1905 until November 1908, and his third from June 1909 - April 1910. He was leader of the Protectionist Party for his first two terms, before the merging of the Protectionsists and the Anti-Socialist Party in response to the 1908 forming of the Australian Labor Party. His third Prime Ministerial term was served as leader of the resulting Commonwealth Liberal Party.