One 24-year-old man told a court in Wuppertal that the group had carried out the attack in despair at violence in their homeland between the Israeli armed forces and Palestinians.
But while they wanted to "send a signal", he say they did not want to set fire to the place of worship or hurt anyone.
The man's two accomplices, an 18-year-old and a 29-year-old, admitted their parts in the attack as well.
Armed with home-made firebombs, the men approached the synagogue and threw the makeshift weapons on the night of Sunday July 28th.
A security camera at a petrol station captured two of the accused filling bottles with diesel, while a neighbour alerted the police.
Investigators said that the Molotov cocktails were amateurishly put together.
"We threw the bottles, both the others ran away and I stayed," the 24-year-old said.
"Two bottles hit the door and the wall. Three didn't reach the building, we were really drunk."
"Two of the accused are from West Jordan, where nothing happened [last summer]. I believe this is pure anti-Semitism", Leonid Goldberg, President of the Jewish community in Wuppertal, said after sitting through the court hearing.
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