It is evident from miscellaneous reports by Spanish Conquistadores that, at the time of the Spanish conquest, avocados were grown from northern Mexico south through Central America into north-western South America and south in the Andean region as far as Peru (where the avocado had been introduced shortly before the conquest), as well as into the Andean region of Venezuela.
The Aztecs used the avocado as a sex stimulant and the Aztec name for avocado was ahuacatl, meaning "testicle." In the pre-Incan city of Chanchan, archaeologists have unearthed a large water jar, dated around 900 A.D., in the shape of an avocado.
1518 - Martin Fernandez de Enciso (1470-1528), Spanish conquistador and cosmographer, wrote the first published record that describes the avocado in his book, Suma De Geografia Que Trata De Todas Las Partidas Del Mundo, as commonly grown near Santa Marta, Colombia. This was the first account in Spanish of the discoveries in the New World.
1519 -Spanish soldier of fortune Hernando Cortez (1485-1547) set foot in Mexico City, the first white man to do so. Cortez found that the avocado was a staple in the native diet
1526 - Fernandez de Oviedo (1478-1557), historian to the conquistadores, wrote the following on avocados trees he saw along the north coast of Colombia: "In the center of the fruit is a seed like a peeled chestnut. And between this and the rind is the part which is eaten, which is abundant, and is a paste similar to butter and of very good taste."
1550 - The Spanish name, Aguacate, was first used by Pedro de Cieza de Leon (1518-1554), Spanish conquistador and historian, in a journal of his travels written in 1550. He noted that at that time the avocado grew in Panama, Ecuador, Colombia, and Peru.
1554 - The first mention of the avocado as growing in Mexico, was made by Francisco Cervantes Salazar in 1554. In his book Crónica de la Nueva España (Chronicles of New Spain), he listed the avocado among fruits sold in the market of Tenochtitlan (the name for Mexico City at that time).
The Spanish conquistadors also discovered a unique use for the avocado seed. The seed yields a milky liquid that becomes red when exposed to air. The Spaniards found they could use this reddish brown or even blackish indelible liquid as ink to be used on documents. Some of these documents are still in existence today.
1672 -W. Hughes, physician to King Charles II of England, in his visit to Jamaica, wrote that the avocado was "One of the most rare and pleasant fruits of the island. It nourisheth and strengtheneth the body, corroborating the spirits and procuring lust exceedingly."
1700s - European sailors in the 1700s called it midshipman's butter because they liked to spread it on hardtack biscuits
1833 - Judge Henry Perrine planted the first avocado tree in Florida.
1856 -.The California State Agricultural Society Report for 1856 stated that Thomas J. White grew the avocado in Los Angeles.
1871 - In California, the first successful introduction of avocado trees was planted by Judge R. B. Ord of Santa Barbara, who secured the trees from Mexico in 1871.
1879 - The oldest living tree is found on the University of California, Berkeley campus and was planted in 1879.
1892 - In other southern California locations, avocados were planted by various people who introduced and planted seed from Mexico and Guatemala. In the early 1890's, Juan Murrieta of Los Angeles became interested in the avocado and imported a large amount of thick-skinned fruit from Atlixco, Mexico. He distributed some of the seeds of these fruits among his friends and planted the others. From this group of seedling trees, came a number of the varieties that first attracted attention as promising commercial fruits.
1895 - In 1895, Young Charles Delmonico and Ranhofer introduced New York to the "alligator pear." or avocado, which had been newly imported from South America. Ranhofer had known of the avocado -- he mentions the avocado in his book, The Epicurean, which he published the previous year -- but until 1895 he had been unable to secure a supply of the buttery fruit.
1911 - Frederick O. Popenoe, owner of the West Indian Gardens of Altadena, California, sent Carl Schmidt to Mexico (Mexico City, Puebla, and Atlixco) to search for avocados of outstanding quality and to locate the trees from which they came. Schmidt, who located what turned out to be the Fuerte as a dooryard tree in Atlixco, Mexico. Only one of the trees he brought back survived the great freeze of 1913 in California. This surviving tree was given the name Fuerte, Spanish for "vigorous." Schmidt said, "Two years later came the big freeze. In the spring when we began to take stock of damage, it was the Fuerte that came through and it was the only avocado that survived. It thus proved itself adaptable to our temperatures."
The Fuerte tree created California's avocado industry. Carl Schmidt was compelled to tell and retell the story of his fortuitous discovery of the Fuerte avocado. “Popenoe was a nut -- an imaginative, idealistic nut without which our nation would suffer and certainly make little progress."
Source : http://whatscookingamerica.net/avacado.htm