The first attempt at any kind of world championship was in 1912, when a three-way series was arranged between the then current Test playing nations, Australia, England and South Africa. No similar events were held again until 1975.
The first ICC World Cup (officially called the Prudential Cup) was in 1975, hosted by England (see full list of host countries). This tournament included the six Test-playing nations (England, Australia, New Zealand, West Indies, India and Pakistan), who were joined by Sri Lanka and East Africa.
Following the success of this tournament, it was repeated in 1979 and 1983 in England. After this, the tournament moved to be played in other countries, maintaining a four-year cycle.
60 overs were used for the first three world cups. This was reduced to 50 in 1987 and has been that way since. The women have held a cricket world cup since 1975.
The 2019 World Cup featured only 10 teams, a decrease from the 14 teams which featured at the previous World Cups in 2011 and 2015. As there are now 12 test playing nations, this means that it is not possible for the tournament to include all Test nations.