To obtain this achievement you need to completely fill all of the original policy trees across any number of playthroughs. Note the reworked ideology system in Brave New World
does not count for getting this achievement nor do the new culture trees it introduced. You will need to disable BNW to unlock it. To do so go to DLC in the main menu and uncheck it.
You will get enough culture to fill five to six trees over a typical playthrough. Also, Piety and Rationalism are mutually exclusive as are the three Ideologies. Alternate your playstyle slightly over three playthroughs and you'll get it naturally easily enough.
Otherwise, set your start to Information Age, found your city, and take one turn. The choose policy prompt will flash. Put everything into whichever tree you're going for. You should have enough culture to completely unlock it. Restart the game for each tree and the achievement will be yours.
You will also unlock the following achievements in getting this one: