The smaller tributaries of these rivers of Sonora are often only dry canyons in the dry season.
In 1853 a filibustering expedition against Sonora under William Walker took possession of La Paz and proclaimed a republic consisting of Sonora and the peninsula.
Near the end of the century Sonora and Sinaloa were divided into two districts, in 1767 the Jesuit missions were secularized, in 1779 the government of the province was definitely organized by Caballero de Croix, and in 1783 Arizpe became the provincial capital.
The first recorded person of European descent to enter the limits of Nevada was Francisco Garces (1738-1781), of the Order of St Francis, who set out from Sonora in 1775 and passed through what is now the extreme southern corner of the state on his way to California.
The largest rivers of Mexico are: the Rio Grande de Santiago, called the Lerma above Lake Chapala, rising in the state of Mexico and flowing westward across Guanajuato, Jalisco and Tepic to the Pacific coast, with a total length of 540 m., celebrated for its deep canyons and waterfalls; the Rio de las Balsas, or Mescala, which rises in Tlaxcala and flows south and west to the Pacific with a course of 426 m.; the Yaqui, which rises in western Chihuahua and, after breaking through the northern ranges of the Sierra Madre Occidental, flows south-westerly across Sonora to the Gulf of California, with a length of 390 m.; the Grijalva, also called the Chiapas on its upper course, which has its sources in the state of Chiapas and flows north-west and north across Tabasco to the Gulf of Mexico, with a total length of 350 m.; the Fuerte, which rises in southern Chihuahua and, after breaking through the sierras, flows south-west across Sinaloa to the Gulf of California, with a course of 340 m.; the Usumacinta, which is formed by the confluence of the Chixoy and Pasion on the east frontier of Chiapas, and flows north-west across Tabasco to the Grijalva, with a course of 330 m.; and the Panuco, which has its source in the north-west of the state of Mexico and flows north-eastward to the Gulf of Mexico.
Fearing an attack from the mainland, the filibusters first withdrew to La Ensenada, near the American frontier, and then in the following year broke up altogether during an attempt to invade Sonora by land.
The Totonacs inhabit northern Vera Cruz and speak a language related to that of the Mayas; the Tarascos form a small group living in Michoacan; the Matlanzingos, or Matlaltzincas, live near the Tarascos, the savage Apaches, a nomadic group of tribes ranging from Durango northward into the United States; the Opata-Pima group, inhabiting the western plateau region from Sonora and Chihuahua south to Guadalajara, is sometimes classed as a branch of the Nahuatlaca; the Seris, a very small family of savages, occupy Tiburon Island and the adjacent mainland of Sonora; and the Guaicuros, or Yumas, are to be found in the northern part of the peninsula of Lower California.
Bancroft's The Native Races of the Pacific States of North America, of which the principal authorities are the Noticias del Estado de Chihuahua of Escudero, who visited the ruins in 1819; an article in the first volume of the Album Mexicano, the author of which was at Casas Grandes in 1842; and the Personal Narrative of Explorations and Incidents in Texas, New Mexico, California, Sonora and Chihuahua (1854), by John Russell Bartlett, who explored the locality in 1851.
Arizona history begins with the arrival in Sonora in 1536 of Alvar Nunez Cabeza de Vaca, who, although he had not entered Arizona or New Mexico, had heard of them, and by his stories incited the Spaniards to explore the unknown north in hope of wealth.
The Gwin party hoped to divide California into two states and hand the southern over to slavery; on the eve of the Civil War it considered the scheme of a Pacific coast republic. The decade 1850-1860 was also marked by the activity of filibusters against Sonora and Central America.