Complex sentence: The last Prime Minister who was a peer was Baron Kijuro Shidehara, who served as Prime Minister from October 1945 to May 1946, and the peerage was abolished by the Supreme Commander, Allied Powers in October 1947.
Split into simpler sentences: The last Prime Minister who was a peer was Baron Kijuro Shidehara, who served as Prime Minister from October 1945 to May 1946. The peerage was abolished by the Supreme Commander, Allied Powers in October 1947.