Science around measuring time has existed since long before history, probably before we were even human. I'm sure homo habilus looked at the position of the sun and estimated when it would get dark, I'm sure he looked over a great distance he had to travel and estimated how long it would take.
Trying to identify what time actually is is new. Einstein discovered that it was woven into reality and not separate from space. The idea of entropy defining an arrow for time came from a number of people working for Newton's laws of thermodynamics.
We still really have no idea what time is, and why it's different than other dimensions. You can define it mathematically, but not really describe it.