Outlook is a god-awful application which is forced upon knowledge workers the world over. Worse yet, once you get familiar with all of the obscure settings and context menus in Outlook, along comes another horrendous UI redesign wherein Microsoft rearranges the buttons and settings.
If you want to view multiple calendars, the default setting brings them up side-by-side. This is totally useless; any other modern calendar defaults to having the events overlaid (merged).
Undoubtedly, if you are reading this, you are hammering Google to try to figure out how to accomplish this feat. You probably already figured out how to do this with previous versions of Outlook. Well Microsoft moved the options.
Here is how to do it.
Then you will now have a merged monthly calendar view, and you can now see all of your appointments and events in a merged view, just as it is in iCal or Google calendar.