General Mwathethe is the Chief of Defence Forces following his promotion and appointment on 17 April 2015. He has held various command appointments including Vice Chief of the Defence Forces, Commander Kenya Navy, Deputy Commander Kenya Navy, Kenya Navy logistics Commander, Base Commander Mtongwe and Fleet Commander. His other appointments included Chief of Systems & Procurement, Department of Defence, Command of individual Kenya Navy Ships, SOII Operations at Navy Headquarters, 86 Squadron Commander, and SOI Co-ordination at the Department of Defence.
His other professional and military training include International Sub-Lieutenants Course (UK), International Principal Warfare (IPWO) Course (UK), Missiles Course (ITALY) and the Royal Naval Staff College, Greenwich, (UK) in 1989. He also attended the Defence Resource Management Course in Monterey, USA in 1998, and the National Defence College in Nairobi, Kenya in 2000.
He also served with the United Nations as a Military Observer in Kuwait/Iraq and Yugoslavia in 1991/92. His decorations include Distinguished Conduct Order (DCO), Moran of the Burning Spear (MBS), among others.
General Samson J Mwathethe was born in Malindi and educated at Shimo La Tewa and Sacred Heart High Schools Mombasa, before joining the Kenya Navy in April 1978. He was commissioned in 1980 as a Seaman Officer after attending Britannia Royal Naval College, Dartmouth.