Origin
The Houthi movement emerged from the Zaidi Shia revivalist movement in northern Yemen in the 1990s, originally as a religious and social reform organisation. Multiple rounds of conflict with the Yemeni government from 2004 evolved into a full insurgency. The movement seized the Yemeni capital Sanaa in 2014 and has controlled north Yemen and exercised sovereign-like functions there since 2015.
The Saudi-led intervention
From 2015, a Saudi-led coalition intervened militarily against the Houthis. The war produced one of the worst humanitarian crises of the period and substantial damage to Yemeni infrastructure. A de-escalation framework reached in 2022–2023 reduced direct Saudi-Houthi exchanges; the post-October-2023 phase saw Houthi capabilities redirect to maritime targets in the Red Sea.
The Red Sea campaign
From late 2023 the Houthis began attacking shipping in the Red Sea and Bab el-Mandeb, asserting that they were targeting Israel-linked vessels in response to events in Gaza. The campaign disrupted commercial shipping through the Suez Canal route, pushed major carriers to reroute around the Cape of Good Hope, and produced freight-rate and insurance-premium effects far beyond the immediate participants.
Iran alignment vs operational independence
The Houthis are clearly Iran-aligned: they share ideological orientation, receive material support, and are integrated into the broader "axis of resistance" framing. They are also clearly operationally independent: they pursue their own domestic objectives, escalate or de-escalate on their own timelines, and have at points acted contrary to what an Iranian-directed actor would have done. Both things are true.