If anything - Star Wars copied Battlestar Galactica
From the start, the original Battlestar Galactica was fighting an uphill battle. Many dismissed it as a Star Wars rip-off (George Lucas even sued), the cost of pre-CGI special effects was crippling - especially for a weekly TV series, and what was originally intended to be a series of TV movies was rushed into production as a weekly series at the insistence of the network.
And the result - while it had its moments - frankly wasn't always pretty. The special effects - while impressive for a 70s TV show - had to be used over and over again to minimize costs. The scripts were uneven to say the least, and some of the stories felt like a high-school term paper that had been put off until the night before. To be blunt, it really isn't all that surprising it only lasted a single season.
For all its shortcomings, however, the original series had flashes of brilliance - and at least in my opinion is probably the most influential sci fi series ever.
First, while it might not have invented the dystopian sci fi genre - it arguably did invent the ENTERTAINING dystopian sci fi genre. Think about it - until Battlestar Galactica, all dystopian sci fi films (Logan's Run, Soylent Green, A Boy and His Dog, even Lucas's earlier sci fi effort THX 1138) were all depressing, preachy movies that seemed to mostly care about making us feel ashamed of ourselves as a race. Battlestar Galactica - despite its premise of machines pushing humanity to the edge of extinction - wanted nothing more than to entertain us. And while it might have only done that for a single season, it paved the way for Heavy Metal, Mad Max, The Terminator franchise, and many other dystopian films that are also ripping good yarns. In this new breed of movies, the future may have been bleak - but it also made a hell of a good backdrop for fast-paced action and adventure.
Second, it introduced the concept of the story arc to science fiction. Before Battlestar Galactica, story arcs were pretty much confined to daytime soap operas. The original Star Trek may have had better writing overall, but each episode was entirely self-contained and had nothing in the way of ongoing drama and intrigue. Battlestar Galactica on the other hand presented itself as an ongoing struggle to survive and stay one step ahead of the Cylon empire. And while this may not have entirely worked for the original Battlestar Galactica during its run, it was undeniably gutsy for the show to test pilot a formula that would become the driving force of sci fi series such as Lost and the 2006 Battlestar Galactica reboot.
Finally, while George Lucas may have sued on the grounds the show was copying Star Wars - it's hard not to notice he himself seemed to have borrowed at least few pages from Battlestar Galactica for the Star Wars sequels. Believe it or not, Star Wars was originally supposed to be a stand-alone movie - with an implicit assumption that the empire was destroyed along with the Death Star at the end of the first movie. Sure, the success of the first Star Wars movie guaranteed there would be sequels - but would they have continued the same story-line of the rebellion vs. the empire were it not for Battlestar Galactica? Would the first sequel have had the wonderful plot-twist of Darth Vader turning out to be Luke's father?
And the most popular Star Wars character - Han Solo - actually seems to have borrowed heavily from the most popular Battlestar Galactica character - Starbuck - rather than the other way around. While both Han and Starbuck were the resident bad boys of their universes from the start - Starbuck was the first to be presented as a nearly invincible pilot and ladies' man. Again, think about it - in the original Star Wars, we actually saw next to nothing of Han's super-human piloting abilities that were so prominent in the sequels. Really all he did was pull the hyperspace lever. And he wasn't exactly a lady-killer in the first movie either; constantly getting blown off and insulted by a less-than-charmed Leia. If anything, Luke seemed to a lot closer to getting into (his sister, just not at the time) Leia's pants than Han. Along comes Battlestar Galactica - with its hotshot lady-killer pilot Starbuck. Then all of a sudden Han becomes the clear winner of Leia's hand starting with Empire.
I noticed that Lucas didn't complain at all when the Battlestar Galactica reboot came out. Kinda wonder if he had come around to realizing how much he and the rest of sci fi owes to the original series.