Short answers, pulled from the story.
Kartir, the Zoroastrian mowbadān-mowbad, ordered the destruction of several Buddhist monasteries located in what is now Afghanistan. This campaign targeted the amalgam of Buddhism and Zoroastrianism known as Buddha-Mazda which Kartir viewed as heresy.
King Mihirakula ruled starting in 515 and actively suppressed Buddhism by destroying monasteries as far away as modern-day Allahabad. His son later reversed this policy allowing some recovery after the initial wave of destruction.
Ikhtiar Uddin Muhammad Bin Bakhtiyar Khilji invaded Magadha and destroyed the Buddhist shrines at Nalanda, Vikramasila, and Odantapuri. Qutb-ud-din Aybak left defenseless territories that were the heart of Buddhist India in 1193 before this invasion occurred.
A specific historical campaign ended the independent Buddhist state of Khotan through forced conversion and temple destruction around 1006 CE. Yusuf Qadir Khan conquered Khotan ending its existence as an independent state following a war described as a Muslim Jihad.
The Khmer Rouge regime from 1975 to 1979 destroyed a third of Cambodia's monasteries and massacred 25,000 monks. Pol Pot believed Buddhism was a decadent affectation and sought to eliminate its mark on the nation.
The Kaukhali Massacre on the 25th of March 1980 saw an estimated 300 Chakma and Marma Buddhists killed. Between 1980 and 1995 the Bangladesh Army and Muslim settlers committed at least 13 major massacres against indigenous Buddhist people in the Chittagong Hill Tracts.