His brothers James and John Telemachus and his nephew Robert Ward Johnson were all members of the House of Representatives, and, in the case of Robert Ward, a Senator as well.

Education
Johnson attended Transylvania University in Lexington, Kentucky.

Military
Johnson was commissioned a Colonel of Kentucky Volunteers and commanded a regiment in engagements against the British in Lower Canada in 1813. He was credited by some with personally killing the Shawnee leader Tecumseh during the Battle of the Thames; despite the doubtful accuracy of this claim ("Rumpsey Dumpsey, He Shot Tecumseh"), Johnson would later use it to good effect in his political career.

Career
He was admitted to the Kentucky bar in 1802.

Elected office

Kentucky House of Representatives
Johnson was a member of the Kentucky House of Representatives from 1804-1806 and again in 1819. Johnson was again elected to the Kentucky House of Representatives in 1850, but he died in Frankfort, Kentucky soon after taking his seat.

United States House of Representatives
Johnson was elected as a Democratic-Republican to the Tenth and to the five succeeding Congresses (March 4, 1807-March 3, 1819). He was chairman of the Committee on Claims and the Committee on Expenditures in the Department of War. After serving in the U.S. Senate, he returned to the House, elected to the 21st Congress and to the three succeeding Congresses (March 4, 1829–March 3, 1837) He was chairman of the Committee on Post Office and Post Roads and the Committee on Military Affairs.

United States Senate
Johnson was elected to the United States Senate to fill the vacancy caused by the resignation of John J. Crittenden, and was reelected and served from December 10, 1819 to March 3, 1829. He was an unsuccessful candidate for reelection in 1829.

Vice-President
Johnson was selected as Martin Van Buren's Vice President by the Senate on February 8, 1837, after losing the support of some of his Presidential electors due to his relationship with Julia Chinn, a family former slave. He served as Vice President from March 4, 1837, to March 3, 1841.

Grave and legacy
Johnson is interred in the Frankfort Cemetery, in Frankfort, Kentucky.

Named for Johnson are counties in Iowa, Kentucky, Missouri and Nebraska.

Johnson County, Illinois was named for Johnson in 1812, even before he claimed to have killed Tecumseh.

Quotation

“What other nations call religious toleration, we call religious rights. They are not exercised in virtue of governmental indulgence, but as rights, of which government cannot deprive any portion of citizens, however small. Despotic power may invade those rights, but justice still confirms them. Let the national legislature once perform an act which involves the decision of a religious controversy, and it will have passed its legitimate bounds. The precedent will then be established, and the foundation laid for that ursurpation of the Divine prerogative in this country, which has been the desolating scourge to the fairest portions of the old world. Our Constitution recognises no other power than that of persuasion, for enforcing religious observances. Let the professors of Christianity recommend their religion by deeds of benevolence -- by Christian meekness -- by lives of temperance and holiness. Let them combine their efforts to instruct the ignorant -- to relieve the widow and the orphan -- to promulgate to the world the gospel of their Savior, recommending its precepts by their habitual example: government will find its legitimate object in protecting them. It cannot oppose them, and they will not need its aid. Their moral influence will then do infinitely more to advance the true interests of religion, than any measures which they may call on Congress to enact.”