PIE base ‘to mount up, grow’.
Other derivatives include deliver, from Latin līber ‘free’, cognate with Greek eleutheros ‘free; noble’, in contrast to ‘being a slave’. This probably originally meant ‘belonging to the people’, although the precise semantic development is obscure. Via another path, also root of German Leute ‘nation, people’.
[Pokorny *leudh-1 ‘to grow up; people; free’, pp. 684–685.]