Divorced Parents

I might discuss it directly with them. Just ask if they would be comfortable sitting next to one another at the ceremony (perhaps with their spouses behind them). Another option would be to have one parent (and spouse) in the front row and the other directly behind. Unless your FS's parents have passed, their parents will typically sit in the front row on the opposite side.

I don’t see why they can’t just sit together like civilized adults.

My parents are divorced and my mom has been remarried a long time. My dad makes an issue out of everything. I’m not making a ceremony seating thing. Just sit wherever. Less stress for me

View Quoted Comment Not everyone has civilized adults as parents

When I married my first husband, his parents were divorced and both had partners. They also hate each other (even now over 20 years post divorce). We sat from the aisle his mom and her boyfriend followed by his dad and his girlfriend. His mom said something at first and we told her that if she didn’t want to sit there, she could sit in the back. I’d sit them next to their partners, but all of them in the front row.

View Quoted Comment She said they are decent to each other. And even if not, it’s not her job to accommodate their petty behavior.

Do you have to assign seats for the ceremony? We are not doing this. Let guests figure it out.
For our reception, we are assigning tables and guests can sit in whatever seats they want.

View Quoted Comment For the guests no sides but I want to keep the first two rows on either side open for immediate family. Reception they can all sit wherever they want.

At my first wedding my divorced parents sat together with my mom’s significant other (that she ended up marrying). When my dad walked me down the aisle and was asked who gives this woman away, or whatever was asked he said “her mother and I do”. They weren’t besties but were civil and could be a unified front for my wedding day.

View Quoted Comment

Unfortunately some people can't do more than simply tolerate each other after a bitter divorce.

OP: I sat them on opposite sides with their spouse/date in the front row. My parents are ridiculously childish whenever we get together and I try to keep them apart. My mom still ended up annoying my dad on purpose during pictures. And then my grandma tried to start a fight with him after getting drunk even though our wedding was dry. My mom ended up tossing her and I didn't know anything had happened thank God. So depending on how your parents act, opposite sides seem to be the best. My dad also walked me down the aisle so there was additional separation.