Short answers, pulled from the story.
The oldest known oil paintings survive in the rock-cut caves of Bamiyan, Afghanistan. These Buddhist murals date back to the 7th century AD and display a sophisticated use of drying oils as binders for pigments.
This technique remained unknown in Europe for another 900 years or so after its use in Asia. Early Netherlandish painters like Jan van Eyck and Robert Campin made oil the usual medium during the early and mid-15th century.
Linseed oil comes from flax seeds and serves as the most general purpose drying oil for artists. Painters add siccatives to accelerate drying time and resins to adjust the sheen of the paint.
John Goffe Rand invented the squeezable metal tube in 1841 to solve portability issues for artists. The collapsible tube enabled relatively convenient plein air painting for the first time.
Venice led the move toward canvas supports because sail-canvas was easily available and cheaper than wood. Canvas for sails was made in Venice and offered a cheaper alternative for larger images.