The first 8-bit microprocessor, the TMX 1795 had the same architecture as the 8008 but was built months before the 8008. Never sold commercially, this Texas Instruments processor is now almost forgotten even though it had a huge impact on the computer industry. In this article, I present the surprising history of the TMX 1795 in detail, look at other early processors, and explain how the TMX 1795 almost became the first microprocessor. (Originally I thought the TMX 1795 was the first microprocessor, but it appears that the 4004 slightly beat it.)
Very detailed article about early micrprocessors, including lots of pretty pictures.