Investigators found that the woman from Allgäu in southern Germany had moved to Syria with her daughters – then aged three and seven – in January 2014.
While there, she married a jihadist fighting for terrorist organization Jabhat al-Nusra.
The accused, who had converted to Islam in 2012 from her former Catholic religion, previously worked in a shop.
Following her conversion, she came into contact online with a woman from Hesse, who told her that she had moved to Syria with her husband, a 'holy warrior' fighting against the Assad regime.
That convinced her to go to Syria with her children and join a jihadist group aiming to establish an Islamic religious state under sharia law.
Her correspondent suggested that she should become the second wife of her husband when she arrived, so that she would have someone to take care of her.
Her new husband trained her in the use of the weapons the family had, including firearms and hand grenades, in preparation for a possible attack on Syrian army troops.
But when she returned to Germany in May 2014, she was arrested.
The father of her children had reported her to the authorities because she had failed to keep up their arrangements for shared custody.
If convicted, she would face up to 10 years in jail for the crime of preparing a serious crime against the state.
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