Short answers, pulled from the story.
Historians estimate that between 250,000 and 500,000 Roma and Sinti were killed by Nazi Germany and its collaborators during World War II. Some scholars, including Sybil Milton, place the death toll as high as between half a million and one and a half million. Zbigniew Brzezinski estimated 800,000 killed through Nazi actions.
Systematic Nazi persecution of the Roma began in 1933, when Hitler came to power and anti-Gypsy laws already in effect were expanded. On the 26th of November 1935, Germany extended the Nuremberg Laws to apply to the Roma, classifying them as enemies of the race-based state. Mass deportations to Auschwitz-Birkenau were ordered in December 1942.
Some 23,000 Roma, Sinti, and Lalleri were deported to Auschwitz-Birkenau, where they were housed in a dedicated compound called the Gypsy family camp. On the 2nd of August 1944, the SS murdered nearly 2,898 of the remaining inmates, most of them ill, elderly, women, and children, in the gas chambers. At least 19,000 of the 23,000 sent to Auschwitz were murdered there.
West Germany officially recognized the genocide of the Sinti and Roma in 1982, when Chancellor Helmut Schmidt made the acknowledgment in a speech. Reparations had only become accessible in small amounts from 1979 onward, after the West German Federal Parliament declared that Nazi persecution of Roma was racially motivated.
Porajmos is a term meaning "devouring" or "destruction" in some dialects of the Romani language, used to refer to the genocide of Roma during World War II. It was introduced by Ian Hancock, director of the Romani Archives and Documentation Center at the University of Texas at Austin, in the early 1990s, chosen from suggestions made during an informal conversation in 1993.
In May 1944, Roma prisoners in the Gypsy family camp at Auschwitz-Birkenau refused an order to come out for liquidation, having armed themselves with iron pipes, shovels, and other tools. The SS withdrew without confronting them directly. The delay lasted several months before the SS returned on the 2nd of August 1944 to murder the remaining 2,898 inmates. Roma Resistance Day is observed on the 16th of May to commemorate that 1944 uprising.