The Mexican Frontier, 1821–1846 published by other historians. This work was supplemented by additional primary materials which he discovered in the archives that allowed him to delve further into certain areas. "The Mexican Frontier" examines the southwestern United States, specifically the areas now known as Arizona, California, New Mexico, and Texas, in the twenty-five years between Mexico's independence from Spain and the beginning of the Mexican–American War. This resulted in the transfer of control of the border areas to the United States. In the early days of the Republic of Mexico, these areas comprised its northern border, including the territories of Alta California and
Battle of the Trench (1821) Battle of the Trench (1821) The Battle of the Trench () was fought near Tripolitsa in Arcadia in August 1821 during the first year of the Greek War of Independence between the Greek revolutionary forces led by Theodoros Kolokotronis and the Ottoman garrison of Tripolitsa. The battle ended with the complete victory of the Greeks. In August 1821, Greeks began the siege of Tripolitsa. The Ottomans who were besieged in the city attempted several night sallies in order to find supplies. When Theodoros Kolokotronis was called by the besiegers to take over command of the siege, he therefore ordered the