how many teams were there then?
Thirteen teams
1930 FIFA World Cup
Thirteen teams (seven from South America, four from Europe and two from North America) entered the tournament. 
who have won the world cup the most times Brazil who is responsible for conducting this? FIFA, the sport's global governing body when did they start this competition? 1930 who were the winners then? Uruguay
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1930 FIFA World Cup [SEP] Introduction
Only a few European teams chose to participate because of the difficulty of travelling to South America. The teams were divided into four groups, with the winner of each group progressing to the semi-finals. The first two World Cup matches took place simultaneously and were won by France and the United States, who defeated Mexico 4–1 and Belgium 3–0, respectively. Lucien Laurent of France scored the first goal in World Cup history, while that day United States goalkeeper Jimmy Douglas posted the first "clean sheet" in the tournament. Argentina, Uruguay, the United States and Yugoslavia each won their respective groups to qualify for the semi-finals.