Q: Why can I not get two pages files in split view

Try System Preferences > Mission Control > Displays have separate spaces = "check"

Please ignore.  Barney-15E's response is correct.

Split View is a modification of Full Screen which only works on Apps, not Document windows. You can only split view two Apps, not two Documents.

It appears that Spilt View is limited by the minimum width of an application's window when in standard view.

If two app takes up more than the full width of the your display when you resize each application window to their minimum width, then they will not be able to be shared in Split View.

On my 15" retina MBP, I can get two pages documents side by side if I change the display resolution towards "more space", but not at the default resolution as each app window's minimum width is greater that half the display's width. On my external 24" display have have no trouble displaying both pages documents side by side.

There is a way: open one document on Pages and other one on Microsoft Word and it works

You need to upgrade Pages. Apple released an update to Pages on October 15, 2015. The update includes Split Screen support for Pages.

1. Update Pages using the App Store app.

2. Open the first document you eventually want in Split View.

3. Open the Second Document.

4. Click and hold on the Green dot in the top left corner of the window. The green dot should contain a small double arrow. After clicking and holding a short time one half of your screen glows blue. Move the document window to the side that glows blue or the other side.

5. Click on the green dot for the other document.

Both Pages documents should now seen in Split View.

Give me an example of a couple of APPS where this is supposed to work. I can't find ANY.

Safari, Mail, iTunes, Pages, etc.

Yes, you can also split view more than one window such as 2 windows in Safari.

If (like me) this still isn't working, then you need to change your resolution settings. Go to system preferences ---->  displays ----> resolution. Change it to something with higher resolution such as "more space" setting, or something larger than default. Basically, with the lower resolution, split screen pages will look crappy so Yosemite won't allow it to work. Change the resolution setting, it will work.

IMO, it's not really solved, because this is all about doing a complicated workaround to a very simple problem. Why can't you view Pages side by side, or 2-up in the viewing or zoom commands. It's completely stupid - why would you REMOVE the ability to do that? It's a routine, standard part of many other programs and was in the last version of THIS program. DUMB - intentional handicapping.

The method in the reply marked as a solution did not work for me.

This is how I managed to get two Pages windows side by side:

1. Open a Pages window.
2. Open another Pages window (⌘N or ⌘O or double click an existing Pages document).
3. Maximise one of them (ie: click on the green button in the top corner of one of the Pages windows).
4. Open Mission Control by pressing F3 / swiping up with three fingers.
5. In Mission Control, drag the Pages window from the desktop to the top of the screen, and drop it onto the maximised Pages desktop/space.

Tip: The "Format" and "Document" panes in Pages take up a lot of space, especially when you've got two Pages windows open in split view. To overcome this issue, simply click on the respective buttons in the ribbon at the right top corner of the window to hide them.

this was the only suggestion that worked for me, thanks !

I have updated to 5.6.2 and still cannot do this.