Many people have often wondered about the origin of this phrase.

Here are the most likely sources:
1. Chivalry. In the ancient past:
When cave dwellers used to hear sound from the outside, they would send the women out of the cave first so that the men could attack the bears and wild animals from behind.
During the middle ages, knights used to place their coat over a puddle of mud, in order to allow women to pass over to the other side safely and cleanly.
2. A love story in Italy.
Two lovers were so in love with one another that they decided to get married. But, due to social circumstances, their parents did not approve of their marriage proposal. As such, the couple decided to die together and so a plan of throwing themselves into the ocean developed.
The man decided to jump first because he did not want to see his lover drowning in front of him. And thus, he jumped into the stormy sea first. And now it was her turn, and yet she just stood there, decided not to jump, and returned back home to her parents.
Thus, after many men learned of this story, they have since decided to play it safe: Ladies First!
3. Women and Children First.
Many people believe this term was created to save the lives of women and children in dangerous and life-threatening situations. Thus, after the Titanic hit the iceberg and sank, 74% of the women onboard were saved, 52% of the children were saved, but only 20% of the men survived.
Now which of these three origins seem right to you? The choice is YOURS.
Or alternatively:
4. The view.
You might have heard this one: “Ladies First” is just a nice way of saying “Let me look at your derrière as you walk in front of me.”