No President of the US can be said to have been "elected by secession", unless possibly Washington himself, if the states ratifying the 1787 Constitution are considered thereby to have "seceded" form the old Confederation, but this is a very questionable notion. Jefferson Davis was elected President of the Confederate States after their secession in 1861, but was of course never President of the US.
Jefferson Davis
when Lincoln was elected president
December 1860 - after Lincoln had been elected as the first president from the newly-formed Republican party.
south carolina
None.
Barack Obama was the first Black president elected.
Barak Obama was first elected as President of the United states in 2008 and was re-elected as president in 2012
Cleveland was elected for his first term in 1884.
Douglas Hyde was the first president of Ireland. He was elected in 1938.
The U.S.As first president elected is George Washington
The first elected president of RUSSIA was Boris Yeltsin.
The first elected President of Iran was Abulhassan Banisadr. He was elected in January of 1980, and impeached in June of 1981.