Theoretically blockchain was the first. The first work on a cryptographically secured chain of blocks was described in 1991 by Stuart Haber and W. Scott Stornetta. In 1992 they incorporated Merkle trees to the design, which improved its efficiency by allowing several document certificates to be collected into one block. But the fist "modern type" blockchain was conceptualized by Satoshi Nakamoto. Although, now blockchain is separated from Bitcoin, Bitcoin can't exist without blockchain.