the very first block was the genesis bock…which is a hash of a New York times magazine article talking about the financial crash of 2007…
The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
the first block contained transactions to be confirmed using hashing
and it was mined by the cpu finding a script solution to the hash…thus confirming the first transactions within the block
see here: Genesis block - Bitcoin Wiki