Is Metallica rock or metal? The answer may not be as simple as you might think.

Sure, us metalheads wouldn't dream of lumping Metallica in with only rock music. Because, let's face it, the long-running band is the biggest heavy metal group on the planet. But aren't there particular Metallica albums and songs that skew more toward hard rock than heavy metal? And further, isn't heavy metal a form of rock music anyway?

Indeed, when considering everything under the hood, "Is Metallica rock or metal?" is a bit of a complicated question. So let's dive in.

Is Metallica Heavy Metal or Rock?

Let's be clear — Metallica are generally considered a heavy metal band. After all, they're one of the pioneering bands of the thrash metal genre that emerged in the 1980s. Without Metallica's Ride the Lightning (1984), Master of Puppets (1986) and …And Justice for All (1988), the rise of thrash would have likely looked very different. And barring those early Metallica works, thrash might not have hit the mainstream vein that it did at all.

But from the 1990s onward, Metallica experimented with different musical paths and incorporated styles from hard rock and even alternative rock into some of their works.

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Let's look at it this way: Say you were a teenage rock fan who had just discovered Metallica around the time of their 1996 album, Load. That effort's first single is the alt-rock song "Until It Sleeps." The next single, "Hero of the Day," follows the same path. And the third Load single, "Mama Said," is country-rock balladry akin to Southern rock or outlaw country.

Metallica in 1986 (Michael Ochs Archive, Getty Images)

Again, if you were that listener and hadn't discovered Metallica's earliest stuff, what kind of band would you label them? (Remember, there was no streaming, YouTube or Wikipedia in 1996.)

Notwithstanding the similar approach taken on 1997's Reload, even when Metallica did get back to metal, it was with a tact focused on the popular styles of the time. 2003's St. Anger is metal, but more so alternative metal or even nu-metal when compared to the early Metallica thrash sound.

All that said, undoubtedly, Metallica were particularly influential in shaping the sound of modern metal. But the band found a big enough following that, by Load (and even somewhat starting with 1991's self-titled "Black Album" — think "Nothing Else Matters"), the act was recording bonafide rock songs meant for the masses.

Rock vs. Metal – What's the Difference?

Still, while Metallica's music may have rock influences — and they have, as we've shown, "gone rock" at some points in their carer — they are primarily recognized as a metal band.

Steve Allen, Getty Images
Metallica in 1990 (Steve Allen, Getty Images)

But, to be pedantic, heavy metal wouldn't exist without rock music. And many of Metallica's influences come from the rock world and beyond — not always metal.

Metal History

Within the annals of music history, rock played a pivotal role in the evolution and development of metal. While the exact origin of heavy metal is hard to nail down, it emerged as a distinct genre in the late 1960s and into the '70s, drawing inspiration from various influences that included rock.

Rock laid the groundwork for metal by pushing the envelope regarding distorted guitars, loud drums and powerful vocals. And as rock evolved, metal came forth. Think Chuck Berry to The Beatles to Led Zeppelin to Black Sabbath. That's the (very simplified) continuum that led to metal.

Come to think of it, a band such as Black Sabbath represented the turning point in metal's development. With Sabbath's heavy guitars and ominous lyrics, their 1970 debut LP often is called the first "true" heavy metal album.

Robert Mora, Getty Images
Metallica in 2003 (Robert Mora, Getty Images)

Other bands, such as Judas Priest and Deep Purple, also contributed to metal's development. And Sabbath, Priest and Purple have all seen shout-outs from Metallica as substantial influences on their music — alongside classic punkers such as the Misfits and hard-rockers such as Thin Lizzy.

Metallica Are Metal, But Not All the Way

So is Metallica rock or metal? With everything we've covered here, we hope you have gained a better appreciation of the question. Again, it's not so cut and dry. If someone says that Metallica are all-the-way metal, another person could make a convincing argument that it's not quite the case.

But whether Metallica are rock or metal — or hard rock or heavy metal, however you want to put it — it isn't that important. The importance lies in the feeling Metallica's music gives you — then, now and forever. Whether it's the blistering thrash of Master of Puppets or the '90s rock of Load, the significance of Metallica's music is within the listener.

So, what do you think? Is Metallica rock or metal?

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