As I mentioned in “Gundam 40th Anniversary“, one of the more intimidating aspects of Gundam is the various timelines. Before I began watching Gundam, I too was intimidated by this aspect. However, it is not nearly as complicated as it first appears.
The first thing to remember is that each timeline is separate. The only exceptions are Turn A Gundam which contains references to other timelines and Gundam Reconguista in G which references a previous timeline. Beyond that, no timeline connects with each other. Therefore, the most important thing to do is to start at the beginning of a timeline. To help with that, I will explain each timeline and where to start within that timeline.
Universal Century
Universal Century can be considered to be the quintessential Gundam timeline and is easily the most developed. The original Mobile Suit Gundam is part of this timeline along with its sequels Mobile Suit Zeta Gundam, Mobile Suit Gundam ZZ and Mobile Suit Victory Gundam. In addition to these TV series, this timeline contains a variety of spin-offs, OVAs and movies. You will see that my most common recommendation will be to start with the first show produced in a timeline which in this case would be the Mobile Suit Gundam TV series or the Mobile Suit Gundam movie trilogy which tells the story of the TV series in a more condensed format. However, for this timeline, I would actually recommend the OVA prequel Mobile Suit Gundam: The Origin which is set before the original series and lays the groundwork for the war and politics as well as providing a wide range of characters with added depth.