Jacob was supposed to marry the princess, everything was arranged, they have been wanting to marry each other for a long time.
But the night before their wedding, her maids told the Jacob that she was not in her chambers and they can't find her. Jacob knew something bad had happened because they loved each other, there was no way that she left on her own.
After searching for her for months, he found out that she was taken by the Ottomans and she was going to be Soltan Mehmet's new wife, against her own will.
So as predicted, Jacob took his whole army to ottom and they entered the castle as the wedding was happening, his sword was bloodied, he killed anyone that came on his way.
When his eyes suddenly landed on her, standing there, in a white dress and crying.