The state court in Celle in northern Germany convicted Ahmad Abdulaziz Abdullah A., who goes by the alias Abu Walaa, of membership in and support for a terrorist organization, the dpa news agency reported.
The court found that Abu Walaa and his network radicalized young people in northern and western Germany and sent them to areas controlled by IS. Three co-defendants were given prison sentences of up to eight years.
The verdict against the 37-year-old Iraqi citizen ended a trial that began in September 2017.
Abu Walaa was the imam at a prominent radical mosque in the northern city of Hildesheim and also organized “Islam seminars” at mosques elsewhere in Germany.
German authorities banned the organization that ran the mosque in March 2017.