The most impactfull moment in part 1 of To Kill a Mockingbird is the scene when Mrs.maudie place catches fire.
It starts when her fireplace is left unattended and her house catches fire. The townspeople move things around their homes to try and prepare for the fire to spread and head out to the scene to help get mrs,maudie's things out of her house. The narrator of this scout is left watching all this through the night,standing out in the cold. She doesn't even notice when boo radley comes up behind her to give her a blanket to shelter her from the cold. Scout doesn't even notice his presence as he too was most likely helping move things during the fire. Perhaps she didn't even recognize him.
It shows how they would come together as a community and how they look out for each other even though they all have separate goals in life. It's further clear that this took place during the great depression especially with how the fire is responded to. It takes quite a while for everyone in the area to come help with the fire as well as prepare their own homes in case they catch a flame. This is because most houses are made out of wood at this time.