Siyar is the branch of Islamic law (fiqh) dealing with international relations, conduct of war, diplomacy, and the treatment of non-Muslims in Islamic governance. The term is the plural of "sirah" (way or conduct) and refers to the behavior of the Islamic state towards others. The science of siyar was pioneered by the great jurist Imam Muhammad ibn al-Hasan al-Shaybani (d. 805 CE), a student of Abu Hanifah, whose work "Al-Siyar al-Kabir" became the foundational text in the field. Al-Shaybani systematically addressed issues of war and peace, drawing on the Quran, Sunnah, and the practice of the early caliphs. Siyar covers a comprehensive range of topics: the rules governing the declaration of war (jihad) and its conduct, including the prohibition of harming civilians, women, children, the elderly, and religious figures; the protection of trees, crops, and property; the treatment of prisoners of war; the laws of truce and peace treaties; diplomatic immunity and the treatment of envoys; the rules of safe conduct (aman) for non-Muslims entering Islamic territory; the status of non-Muslim subjects (dhimmis) and their rights; and the division of spoils (ghanimah). Al-Shaybani's work established ethical rules for warfare over a millennium before the modern Geneva Conventions, emphasizing proportionality, distinction between combatants and non-combatants, and humane treatment of prisoners. Siyar also addresses issues of international trade, contracts between Muslims and non-Muslims, and jurisdiction over crimes committed by or against foreigners. In the modern context, siyar principles inform Islamic perspectives on international law, human rights, and relations between Muslim and non-Muslim states. For Muslims, siyar demonstrates that Islamic law provides comprehensive guidance not only for individual conduct but also for state behavior in the international arena. It reflects the Islamic commitment to justice, mercy, and the rule of law, even in the context of conflict, and provides principles for peaceful coexistence and cooperation with non-Muslim communities and states.