All present-day non-Africans descend from mtDNA haplogroups M and N with TMRCA around 50ka. Three hunter-gatherers from Belgium and France 35-28ka carried hg M absent in modern Europeans. Vast majority of Late Pleistocene and Early Holocene Europeans belonged to U subgroup of N clade. Single rapid dispersal into Eurasia carried both M and N after their divergence around 50ka. European hunter-gatherers survived LGM bottleneck with continuity but lost hg M. Major maternal population replacement occurred in Europe at 14.5ka during Late Glacial. Surviving pre-LGM population diverged around 29ka before LGM. Initial small European founder population grew until 25ka then bottlenecked in refugia. Post-LGM re-expansion followed by influx from separate refugium. No surviving mtDNA from earlier African expansions outside Africa. Basal U lineage found in 33ka Romanian without modern descendants. mtDNA mutation rate estimated at 2.74 × 10−8 per site per year. Climatic events drove genetic bottlenecks and population shifts in early Europeans. hg M reached Western Europe by at least 35ka. Model rejects early separate southern/northern routes for M and N. Late Glacial upheaval replaced post-LGM maternal lineages.