It has been a long 15 years for Jeff Williams, guitarist and singer for the influential indie rock band N.I.L.8.

Playing shows across the country, writing dozens of witty songs and putting out four albums, N.I.L.8 has made a large impact on underground music.

But all things must come to an end sooner or later.

So, after playing music for a decade-and-a-half, N.I.L.8 is calling it quits.

Several circumstances led to the breakup of the band, but Williams said it was not the result of a major dispute between band members.

“When we started this thing, we never wanted it to go downhill,” Williams explained. “I wanted to either do it 100 percent or not do it at all.”

Williams said one of the key reasons for the band’s breakup was because of members’ other commitments. Guitarist Eric White is married, and drummer Walnuts has two kids. Members also wanted to pursue careers.

Getting its start in Springfield, Ill., the four-man band fused elements of punk, ska, hardcore, rap and various other styles. In doing so, N.I.L.8 created one of the most unique and innovative sounds in music today.

In fact, N.I.L.8’s sound was so diverse that even the band members themselves had difficulty categorizing it.

“I don’t know what to call it. I guess it’s hardly core, hardly ska, hardly punk, hardly rap, hardly music,” Williams said, taking time out from his job at a record store in Springfield to comment.

Whatever you want to call it, there is no doubt N.I.L.8 struck many music listeners.

The band began playing initially just for fun with no intention of becoming a nationally-known band.

“Everything we’ve done lately has been really good,” Willliams said. “We did so much more than we ever thought we would.”

He added that 1992 was the year the band started to tour often and take its music more seriously.

“It was just a joke when we started to tour because we had lost our jobs,” Williams said, adding that before 1992 the band only performed about once a month.

But when the band finally did start to tour, N.I.L.8 built a large fan base, networking its fans through a Web page and e-mail newsletter. Soon after, the band enjoyed some commercial success, making enough money to support itself.

Now, the band has sold more than 7,000 albums on Fuse Records, an independent label out of Chicago.

Williams noted playing shows at colleges like the University of Illinois, Eastern Illinois University and Iowa State helped the band quite a bit.

ISU has received the honor of hosting several N.I.L.8 concerts. This school year alone, the band has played two shows at the M-Shop and one at People’s Bar and Grill.

“Playing at the M-Shop was always a lot of fun. Playing at Peoples with House of Large Sizes was actually pretty cool,” Williams said. “It’s cool to get a cool crowd like in Chicago, but at the same time smaller bars and clubs in college towns are really cool, too.”

N.I.L.8 played its last four shows over the weekend of April 10 at Veile’s Planet in its hometown of Springfield.

According to Williams, people came from Iowa, Wisconsin, Kansas and Missouri to enjoy N.I.L.8’s music one last time.

“It was kinda crazy,” Williams said about the band’s last shows.

In its long career, N.I.L.8 has had only one lineup change. The original drummer, Walnuts, was replaced for a while by Lance Reynolds.

However two-and-a-half years ago, Walnuts stepped up to the drums again, returning the band to its original lineup.

Touring almost nonstop for the last seven years, N.I.L.8 could definitely use some rest. After all, it has played roughly 100 shows per year with a long list of well-known bands.

Smashing Pumpkins, Fear, the Blue Meanies and Less Than Jake are just a few of the bands N.I.L.8 has played with.

One highlight of William’s career was receiving a compliment letter from Jello Biafro, the eccentric and outspoken lead singer of the now defunct 1980s punk band the Dead Kennedys.

Williams also recalled N.I.L.8’s first performance at “Rock Against Reagan,” a 1980s political punk show featuring Millions of Dead Cops.

According to Williams, the most interesting material the band has produced is the 1997s album “Doug.” The album took music listeners on a sonic adventure into the quirky, chaotic world of N.I.L.8 with songs like “Land of the Lost,” “Zombie Slut” and William’s personal favorite, “Heatmiser.”

At least in Williams’ mind, the band went out on a good note, with a strong last album.

So what’s the future for the members of N.I.L.8?

According to a newsletter sent to fans via e-mail, Jeff Williams is doing graphic design for a company in Springfield; bassist Bruce Williams is playing in an experimental band called Lo Phatt; guitarist Eric White is looking for a job in the engineering field; and Walnuts is creating Web page design.

In addition, Williams said N.I.L.8 will possibly release a CD of live material, although definite plans have not been made.

Jeff Williams made some final remarks regarding the band’s breakup.

“Thanks for coming to the shows. Even though we closed up shop now, maybe we’ll open up again along the road,” he said.