The earliest tomatoes were tiny berries that grew on low bushes in the Andes Mountains in South America. These plants were taken north where they were domesticated by the pre-Columbian residents of what is now southern Mexico. Distance prevented the early farmers from crossbreeding their new varieties with the original populations. Spaniards took the domesticated varieties back to Europe in the 15th century. European settlers brought them to North America after that.
To save seeds that are true to type- tomato plants must be 10-20 feet away from all other varieties of Solanum lycopersicum. You can harvest viable seeds from one plant. You need 12-15 plants for variety maintenance and you only need 20 plants or more for genetic preservation.
You can learn more about how to plant and save tomato seeds here
The varieties that are currently available for everyone who is willing to grow them for food and seeds from the KASSI Living Seed Commons are listed in alphabetical order here The date indicates when the variety became available in North America.