In 1993, Mark Burgess made CFEngine, the first big open source config management tool, to make the management of the workstations at the the Department of Theoretical Physics at the Oslo University much easier. In 2009, the company CFEngine Enterprise was founded. CFEngine, which uses an imperative approach, is still in use today. Luke Kaines, one of the developers of CFEngine, got frustrated with CFEngine given the inflexibility and usability problems mostly caused by the imperative approach—it's very similar to scripting in that subtle changes in the environment can break the automation. That's why he created Puppet in 2005.
The founder of Ansible, Michael deHaan, started the development of Ansible in 2006. He had many experiences with deployment tooling. He was the main developer of Cobbler (an automated deployment tool), was working at Puppet Enterprise...