Direct proof of use
CAESAR use in the 2014 Yemen Civil War is documented through investigative reporting based on a leaked French military-intelligence assessment and through Amnesty International's separate statement that it had verified French-supplied CAESAR truck-mounted howitzers on the Saudi-Yemeni border.
Disclose reported that, on 25 September 2018, the Saudi Arabian army had 48 CAESAR howitzers positioned on the border with Yemen. The same report said the leaked French military-intelligence map described the guns as backing loyalist troops and Saudi armed forces as they advanced into Yemeni territory.
Sources: Disclose Yemen Papers, Amnesty Leaked Documents, Mediapart Hidden Role
Timeline
Open reporting places Saudi CAESAR systems in the Yemen-war record by 2018. Disclose described a CAESAR howitzer on the Yemen-Saudi border in June 2018, then cited the leaked French intelligence report for 48 Saudi CAESAR guns at the border on 25 September 2018.
Disclose separately traced at least ten additional CAESAR guns from Nexter's Roanne plant to Le Havre in September 2018, where they were loaded aboard the Saudi freighter Bahri Jazan and shipped to Jeddah. That delivery context is separate from direct firing evidence, but it documents continued CAESAR supply to Saudi Arabia during the Yemen war.
Sources: Disclose Yemen Papers, Disclose Secret Shipment
Narrative
The documented CAESAR role in Yemen was border artillery fire support for the Saudi-led side rather than use by Yemeni factions inside the country. The conflict metadata side represented here is Yemeni government and Saudi-led coalition forces, because the sources identify the operator as the Saudi army and connect the guns to support for coalition or loyalist ground operations.
The evidence does not establish a complete fire-mission log for every CAESAR battery. Disclose and Mediapart linked the leaked French military-intelligence map to populated areas in northern Yemen and to several artillery incidents inside the guns' range, while Amnesty's public statement treated CAESAR border use as verified. This record therefore treats the system as documented border artillery in the Yemen war without independently attributing every reported shelling incident to CAESAR fire.
Sources: Disclose Yemen Papers, Mediapart Hidden Role, Amnesty Leaked Documents