Sengoku

Fleet Admiral Sengoku (センゴク元帥 Sengoku Gensui), nicknamed "Sengoku the Buddha" (仏のセンゴク Hotoke no Sengoku), is the supreme commander of all Naval forces in the One Piece world, his status apparent by the life-size seagull attached to his hat. He oversees the workings of the Marines from his base in the Sanctuary of Mariejois, though he is subordinate only to the leaders of the World Government, the Five Elder Stars (Gorōsei). He also has a pet goat, it is possible he might have a Devil fruit power, as he is not only the leader of every Marine, and the fact that some of his Marine subordinates have Devil fruit powers, such as Smoker, Hina, and Aokiji. It's also possible that he may have access to Devil Fruits and gives them to subordinates that are deemed worthy.

He frist appeared in chapter 233, he called in the Shichibukai to discuss the replacement for Crocodile. He told Dolflamingo to quit playing his 'game'. He seems to use Tsuru as his assissent and would get information from her.

He use to be a Admiral 20 years ago and was the one who ordered the Buster Call to Ohara, he had Sakazuki and Kuzan to led the Buster Call.

It was proven that he is extremly loyal to the World Government and does not like anyone questioning the World Government, he believes that the World Government must always be trusted. Having to believe the Oharans are "evil" for breaking the law, bindly doing the World Government's order. He seems to not know that the Oharans don't care about the Ancient Weapons as he seems to be aware that the World Government is actully hidding the real reason to "punish" the Oharans

He even order the Marines ans Agents to find Robin.

Recently, in chapter 438 Garp informed Sengoku about about Luffy about being his grandson but Sengoku got pissed off and ordered him back to Water 7 to capture Luffy. Note: "Sengoku" can be written in kanji as 戦国, meaning "warring states," which is a period of Japanese history.