The protest leaders said they wanted to rid Thailand of the influence of Yingluck and her wealthy brother, the exiled former Prime Minister Thaksin Shinawatra, who was deposed in the country's last military coup in 2006.
The siblings' powerful political movement, which has dominated elections for more than a decade, draws its support from Thailand's populous rural regions in the north and northeast.
But it is unpopular among the Bangkok elites, who accuse it of buying votes through ill-judged, populist policies.
The protesters who campaigned against Yingluck's government claimed Thailand needed reforms to be imposed by an unelected council before any further elections could take place.
With the military's intervention, they appear to have gotten their wish, although some of the protest leaders were taken into custody after the coup.
On Monday, the officer who led the coup, Gen. Prayuth Chan-ocha told reporters there was "no set time period" for when new elections might be held, and he outlined the steps he said his junta plan to take, including setting up a committee to introduce reforms.