server hosting text file question

[DJPenguin]

running a co-op server, I'm looking to experiment as far as which maps factions are playable. could someone explain what the lines in this set of commands means?

add_factions fac_kingdom_1 fac_kingdom_1
add_factions fac_kingdom_2 fac_kingdom_2
add_factions fac_kingdom_3 fac_kingdom_3
add_factions fac_kingdom_4 fac_kingdom_4

 

[DJPenguin]

one other thing. dunno if it's a coincidence, but i don't think i've ever seen cossacks being on the rotation, so they're not played unless voted for. and in that block of text i pasted, there's only 4 lines. when my server is empty i'll try throwing in a fifth line with the number 5 to see if that brings them into the rotation.