Around 1890 the specialty of weightlifting performed with a barbell was first mentioned in a competition. But, of course, lifting heavy objects can be dated back several thousand years before that. At first barbell lifting competitions were often combined with other strength feats – one armed dumbell presses and bridged on the head floor presses are examples.
As with many sports, after probably even hotheaded debates, questioning the way of judging or the rules itself, the sport of weightlifting started to organize itself in Europe, at Olympic and in 1905 at world level (IWF). In the first decade of the European championships the dutch organized them eight times in Rotterdam, Amsterdam and the Hague.
At the Olympic games in Amsterdam (1928) Olympic weightlifting was limited to three exercises – press, snatch, clean & jerk. Guus Scheffer and Jan Verheijen both won a bronze medal only to be followed by Abraham Charité at the 1948 games.
In 1972 the press was deleted. Despite strong women were already in the game of exhibiting strength for many centuries, they could only enter Olympic weightlifting as a sport in the 1987 world championships and in 2000 at the Olympic games.
And just as a remark, bodyweight categories have changed a lot over time. At the moment 10 male and 10 female categories exist. Also international weightlifting has a minimum age standard at 13 (current year minus birth year) and has separate youth, junior and masters age groups. A senior lifter is 15+.