Short answers, pulled from the story.
American chemist William Draper Harkins proposed the concept of nuclear fusion in 1915. This proposal laid the groundwork for future discoveries regarding atomic nuclei combining to release energy.
Mark Oliphant, Paul Harteck, and Ernest Rutherford published an intentional deuterium fusion experiment in May 1934 at the Cavendish Laboratory. A researcher at the University of Michigan made the first observation of deuterium tritium fusion in 1938.
The first true thermonuclear weapon detonation was the 1952 Ivy Mike test of a liquid deuterium-fusing device yielding over ten megatons. This event utilized the full power of a fission blast through the Teller Ulam design.
The Sun fuses 620 million metric tons of hydrogen and makes 616 million metric tons of helium each second. This process occurs in its core at a solar-core temperature of 14 million kelvin.
China's government made fusion a national priority and poured 2.1 billion dollars into a single Chinese state-owned fusion company in 2025. This amount is two and a half times the U.S. Energy Department's annual fusion budget.