Abu Dawud Sulayman ibn al-Ash'ath al-Sijistani (202-275 AH / 817-889 CE) was a prominent hadith scholar and compiler of the Sunan Abu Dawud, one of the six canonical hadith collections (Kutub al-Sittah). Born in Sijistan (modern-day Iran/Afghanistan border), he collected approximately 500,000 hadiths during his travels and selected 4,800 for his Sunan, focusing particularly on hadiths relevant to Islamic jurisprudence (fiqh). He settled in Basra where he taught and died.