Japan has had a history of small scale coastal whaling for centuries, possibly even as far back as the Jomon period (10,000-300 BC). Large scale whaling likely started around the late 17th century, and by the middle of the 20th century Japan - along with its European and American counterparts - was a leading commercial whaler. Japan was not an original member of the IWC, but joined in 1951 and has been a member ever since.
When the commercial whaling moratorium was agreed to in 1982, Japan - like Norway - took out an objection. This objection was withdrawn in 1985, after which Japan started its "scientific research whaling" in 1987.
Today Japan has two research programs: the Japanese Whale Research Program under Special Permit in the Antarctic (JARPA), and the Japanese Whale Research Programme under Special Permit for North Pacific (JARPN). JARPA is a large scale pelagic whaling program using catcher boats to hunt and catch whales, and a factory ship to process them. The whaling vessels spend months at sea. JARPN initially involved the hunting of 100 common minke whales per year by coastal whalers (large scale and small type). The second phase, started in 2000, increased the number of species taken to include 100 common minke whales, 50 Bryde’s whales and 10 sperm whales each year. In 2008 this number was increased to 340 minke, 50 Bryde's, 100 sei and 10 sperm whales.
Since the moratorium took effect, Japanese whalers have reported killing 14 fin, 47 sperm, 592 sei, 446 Brydes, and 11,294 minke whales in their "research" programs - for a total of 12,393 whales.