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
Regiment of Artillery of the Nation Regiment of Artillery of the Nation The Regiment of Artillery of the Nation () was an Argentine regiment established in 1812 and disbanded in 1820. It fought in the Argentine War of Independence. During the times of the Viceroyalty of the Río de la Plata, the artillery was managed by the "Royal Body of Artillery". The Primera Junta, the government since the May Revolution, disbanded it and created instead the "Regiment of Flying Artillery" on May 29, 1810, relocating some members of the former one. The "Regiment of Flying Artillery" was disbanded in 1812, and replaced by the "Regiment of