The strong Saudi influence on the IMU appears to have had its origins in Tahir Yuldashev’s religious training and fundraising activities in the Kingdom.
A unit of roughly 100 to 200 IMU fighters under the leadership of commander Juma Namangani (a.k.a.
Jumaboy Ahmadjonovich Hojiyev, a reputed former Soviet paratrooper in the Soviet war in Afghanistan) gained military experience fighting alongside Islamist factions in the Tajikistan civil war (1992-97) but found no place for the movement in the negotiated settlement of 1997, leading the movement to shift to bases in Afghanistan under the sponsorship of the Taliban.
From there, the IMU launched its 1999-2000 campaign in Tajikistan and Kyrgyzstan which ultimately failed to achieve its goal of entering Uzbekistan and deposing President Karimov (the movement was also targeting the rulers of Kyrgyzstan at this point).
Though the campaign was largely restricted to small-scale attacks and hostage-taking (including the commander of Kyrgyzstan’s Interior Ministry), the militants’ apparent better training and equipment reduced national security forces to chasing the group around the mountains and briefly caused alarm in regional capitals.