Thai military courts on Friday sentenced two people to long prison terms on charges of insulting the monarchy, the heaviest sentences for the crime in the country’s history, lawyers and a legal monitoring group said. In the first case, Pongsak Sriboonpeng, 48, was sentenced to 30 years for six Facebook posts in 2013 and 2014, said his lawyer, Sasinan Thamnithinan. He had originally been sentenced to 60 years, but the time was reduced because he pleaded guilty, Mr. Sasinan said. In the northern city of Chiang Mai, another military court handed down a prison sentence of 28 years, reduced from 56 years, for a 29-year-old woman who also pleaded guilty, said Yingcheep Atchanont, a researcher at the legal monitoring group iLaw. The woman, Sasivimol, who wanted only her first name used, was sentenced for seven Facebook posts that insulted the royal family, the researcher said. Thailand’s lèse-majesté laws are the world’s harshest and make it a crime to defame, insult or threaten the monarchy.