| 1845 |
| March. | The United States determines to annex Texas; W. S. Parrott sent to conciliate Mexico. |
| July. | Texas consents; Taylor proceeds to Corpus Christi. |
| Oct. | 17. | Larkin appointed a confidential agent in California. |
| Nov. | 10. | Slidell ordered to Mexico. |
| Dec. | 20. | Slidell rejected by Herrera. |
| 1846 |
| Jan. | 13. | Taylor ordered to the Rio Grande. |
| Mar. | 8. | Taylor marches from Corpus Christi. |
| 21. | Slidell finally rejected by Paredes. |
| 28. | Taylor reaches the Rio Grande. |
| Apr. | 25. | Thornton attacked. |
| May | 8. | Battle of Palo Alto. |
| 9. | Battle of Resaca de la Palma. |
| 13. | The war bill becomes a law. |
| June | 5. | Kearny’s march to Santa Fe begins. |
| July | 7. | Monterey, California, occupied. |
| 14. | Camargo occupied. |
| Aug. | 4. | Paredes overthrown. |
| 7. | First attack on Alvarado. |
| 13. | Los Angeles, California, occupied. |
| 16. | Santa Anna lands at Vera Cruz. |
| 18. | Kearny takes Santa Fe. |
| 19. | Taylor advances from Camargo. |
| Sept. | 14. | Santa Anna enters Mexico City. |
| 20–24. | Operations at Monterey, Mex. |
| 22–23. | Insurrection in California precipitated. |
| 23. | Wool’s advance from San Antonio begins. |
| 25. | Kearny leaves Santa Fe for California. |
| Oct. | 8. | Santa Anna arrives at San Luis Potosí. |
| Oct. | 15. | Second attack on Alvarado. |
| 24. | San Juan Bautista captured by Perry. |
| 28. | Tampico evacuated by Parrodi. |
| 29. | Wool occupies Monclova. |
| Nov. | 15. | Tampico captured by Conner. |
| 16. | Saltillo occupied by Taylor. |
| 18. | Scott appointed to command the Vera Cruz expedition. |
| Dec. | 5. | Wool occupies Parras. |
| 6. | Kearny’s fight at San Pascual. |
| 25. | Doniphan’s skirmish at El Brazito. |
| 27. | Scott reaches Brazos Id. |
| 29. | Victoria occupied. |
| 1847 |
| Jan. | 3. | Scott orders troops from Taylor. |
| 8. | Fight at the San Gabriel, Calif. |
| 9. | Fight near Los Angeles, Calif. |
| 11. | Mexican law regarding Church property. |
| 28. | Santa Anna’s march against Taylor begins. |
| Feb. | 5. | Taylor places himself at Agua Nueva. |
| 19. | Scott reaches Tampico. |
| 22–23. | Battle of Buena Vista. |
| 27. | Insurrection at Mexico begins. |
| 28. | Battle of Sacramento. |
| Mar. | 9. | Scott lands near Vera Cruz. |
| 29. | Vera Cruz occupied. |
| 30. | Operations in Lower California opened. |
| Apr. | 8. | Scott’s advance from Vera Cruz begins. |
| 18. | Battle of Cerro Gordo; Tuxpán captured by Perry. |
| 19. | Jalapa occupied. |
| May | 15. | Worth enters Puebla. |
| June | 6. | Trist opens negotiations through the British legation. |
| 16. | San Juan Bautista again taken. |
| Aug. | 7. | The advance from Puebla begins. |
| 20. | Battles of Contreras and Churubusco. |
| Aug. 24–Sept. 7. Armistice. |
| Sept. | 8. | Battle of Molino del Rey. |
| 13. | Battle of Chapultepec; the “siege” of Puebla begins. |
| 14. | Mexico City occupied. |
| 22. | Peña y Peña assumes the Presidency. |
| Oct. | 9. | Fight at Huamantla. |
| 20. | Trist reopens negotiations. |
| Nov. | 11. | Mazatlán occupied by Shubrick. |
| 1848 |
| Feb. | 2. | Treaty of peace signed. |
| Mar. | 4–5. | Armistice ratified. |
| 10. | Treaty accepted by U. S. Senate. |
| May | 19, 24. | Treaty accepted by Mexican Congress. |
| 30. | Ratifications of the treaty exchanged. |
| June | 12. | Mexico City evacuated. |
| July | 4. | Treaty proclaimed by President Polk. |