| 1779 September 14 |
Born in Virginia |
| 1809 | Clerk of Second Superior Court of the Territory of Orleans |
| 1811 | Appointed Judge of St. Mary Parish, incorporated at this time from the southern portion of St. Martin |
| 1812 | Member of Constitutional Convention |
| 1817 | Upon the death of William
C. C. Claiborne, Henry Johnson is chosen to fill the vacant seat in
the U. S. Senate. As a Senator Johnson ingratiates himself to the Creole population by working diligently on the murky land claims from French and Spanish land grants and opening federal lands to private settlement. |
| 1823 | Wins re-election to U. S. Senate on a promise not to run for governor next year. |
| 1824-1828 | Governor of Louisiana. During this administration Louisiana made extensive internal improvements. Johnson has a strong commitment to balance and moderation . |
| 1828 | In political manipulations Johnson backs Edward White vs. Edward Livingston for Congress, John Q. Adams for president and P A C Bourguignon Derbigny as governor, but loses his own race for the Senate against Dominique Bouligny - Livingston wins! |
| 1835-39 | Succeeds Edward Douglas White in U. S. House of Representatives |
| 1838 | Johnson tries for the Whig nomination for governor against Andre Bienvenu Roman while Edward Douglas White retakes the Congressional seat. |
| 1842 | Runs for second term as governor as a Whig but defeated by Jacksonian Creole Alexander Mouton |
| 1844 | Elected to fill the vacant seat of Alexander Porter in the U. S. Senate. As Senator he supports bills favoring annexation of Texas and repealing the tariff of 1846 |
| 1849 | Johnson loses a bid to remain in the Senate to a Jacksonian. |
| 1850 | After losing a race for Congress against Bullard (Whig) Johnson retires to Pointe Coupee Parish to practice law. Soon after he dies and is buried on his plantation which lies at the juncture of Bayou Grosse Tete and Bayou Maringouin. |