I watched Gladiator and Gladiator II back to back
I just watched Gladiator and Gladiator II back to back mostly because my 20 year old daughter wasn't born when the original came out and hadn't seen it.
I thought it wouldn't be necessary to watch the first as *spoiler* they all died but it really helped as the second leant heavily on the lore of the original.
The follow up is more action, more spectacle, more complex but perhaps without the emotional connection that made the first a masterpiece, a solid film though and an entertaining watch.