It wasn't so long ago that we disregarded them as mere house pets as well.
Dates and evidence, please. Also, the "we" bit is obviously nonsense as you're going back long before anyone alive today was born. More accurately, you're going to a fictional misrepresentation of a past that didn't really exist.
A random example that comes to mind. One of many, but this one is what pops up from my memory at the moment.
In the late 13th century, a woman called Christina who lived in the village of Coddicote brought a civil law case against a man regarding a dispute over inheritance. Very importantly for the time, he was a noble and she was a commoner. She wasn't even a burgess. She was a peasant. I'm not sure if she was a freeman or not, but at most she was a common freeman peasant. So there was a massive difference in social class, which really mattered in 13th century England. On top of the point most relevant to your claim - she was a woman and he was a man. She brought the case. She represented herself in court. The court ruled in her favour, forcibly taking the shop in question from the nobleman and giving it to her.
There was no question of whether or not a woman could own a business, property, etc. That was a given. There's never been any point in time in recorded history in England (or, before England existed, the part of Britain that later became England) in which that wasn't true. Surviving medieval English records make it clear that it wasn't at all unusual for property and businesses to be owned by women. The authorities in medieval England took great care to record who owned what so they knew who to tax. The extant records are quite extensive. The legal question in that particular court case was one of inheritance and death tax. Her husband died. The shop was taken as death tax. She argued that the shop legally passed immediately to her on her husband's death because the shop was owned by the marriage and on her husband's death she became the sole representative of the marriage. The court agreed. Which was indeed what English law of the time stated - a marriage was a legal entity in those days, much like a business today.
So...dates and evidence for your assertion, please.