@ErikUden Unlike "Capitalism", "Patriarchy" is a very weakly defined word. It is therefore not possible to evaluate the truth of sentences like "Patriarchy existed before capitalism".
Queen Victoria existed before capitalism too. Was that a matriarchy, since the worlds most powerful person was a Woman?
In fact, the oppression of women IS a side conflict, just like any other oppression based on gender, including that of men. Same goes for oppression based on nationality or color of skin.