Pretty far, though the planet would probably be worse off.

Fossil fuels don't really become integral until the 18th century with industrial revolution and the demand for hotter burning furnaces and electricity. Before that charcoal could pretty much do everything that required heat and various tree tars could be used for waterproofing.

There are loads of alternative methods out there or making the same end products from animals and plants. I rememeber reading papers 10 years ago about drop-in replacements for gasoline & gasoline dirivitives made from algae. The ecological damage would have been much greater though as more forests would have to be cut down for wood, seas farmed for algea, and livestock raised for fat.