Answer: They believed that the Natives were "savage beings who lived like animals"
Explanation: You are correct, they weren't nice to natives. It is because the European's had not been accustomed to seeing people who were quite as different as them and therefore they saw themselves as better than the natives ( this is also how racist Europeans saw Africans, hence why slavery started). They didn't respect the Natives' ways and thought that they had the right to take the land even though it rightfully belonged to the Natives.
Hope this helps! Please let me know!