From Lexicanum

Year	Event	Source
	The Dark Age of Technology begins. Humanity begins to colonise the nearby star systems using conventional sub-light spacecraft. The new colonies must rely on local resources, and be completely self-sufficient in all vital areas in order to survive. Ten generations are needed to travel between the more distant of the new colonies and Terra. This continues until M18.	Space Marine by Ian Watson, Galaxy In Flames page 410, by Ben Counter

M14	Timeline	M16