The following is a quote from French prime minister Georges Clemenceau giving his inaugural speech on the 20th of November 1917, during the midst of the first world war.
We present ourselves in the single aim of total war... At home I wage war. Abroad I wage war [...] I shall go on waging war.
The quote illustrates what total war really means for a country. Clemenceau in effect described how the upmost effort would need to be taken in order to win the war that was being waged. This view that the entire society of a nation should be geared towards waging a war was hardly not reciprocated in with the central powers.
Although I do not have a copy of Ludendorff's Der Total Krieg on hand for direct quotation, Ludendorff placed heavily emphasis on the need to increase the capacity of a nation to wage war and that things like politics and the wellbeing of a nations people need to be placed on the backburner in order to achieve that goal. Ludendorff's actions during the first world war largely echo his writings, as he and General Hindenburg basically turned Imperial Germany into a millitary dictatorship as the war progressed to its latter half.
Alongside this, Ludendorff put special emphasis on the idea of a "spiritual unity". This unity represents the collective will of the people to wage the war the nation fights in. Everything about the nation is geared towards fighting; its entertainment, education and culture is first and foremost towards the army. This prussian militarism largely reflects the popular quote of Prussia and by extension the Prussian dominated Germany of being "an army with a state".
While countries such as the United States and Great Britain never really had their military's run their state in the 20th century, its hard to state that when the cards were down, they did not regear the majority of their economy towards the war effort. Tractor factories turned into tank factories, jeeps were being made for the military. Liberty ships in the US were being pumped out at incredible rates to serve in convoys, to the point that these ships were being built in days.
Rationing, a staple of the second world war, were both harsh in things like gasoline and sugar, but fairly lenient in things like wine. I say wine specifically because recently I had gotten my hands on a canadian ration card of wine. In it, I counted 45 tickets left,each permitting the sale of one bottle of wine, issued in 1943 and expiring in 1946. Although definitely focused in war economy, nations like the USA and Canada simply did not need to use the sort of total war that Ludendorff envisioned, though I definitely think it would be hard to say that these two nations were not engaged in a total war.
Which brings us to the next point: the totality of total war. Nation-states fighting a total war only when the other either unconditionally surrenders or collapses. German soil may not have been occupied during the final stages of world war one, but Germany was collapsing at the seams when the armistice was signed. During the second world war, the allied powers did not seek a conditional surrender from any of the axis powers, they wanted an unconditional surrender from all members of the axis.
To put it simply, a total war pretty much never happened before the 20th century. In the title of the question, you mention "looting and pillaging", so lets use one of the most famous examples: The annihilation of Carthage. While in a sense it was destruction, the Carthaginian empire did not put everything they had into stopping the destruction of Carthage from occurring.
You will not find roman plebs being conscripted en masse across several roman provinces to serve in the army. You will not have any empire spanning rationing system during the mongol expansion. A "white peace" is little more than a joke between the central power and the entente when the war keeps dragging on. In short, a total war isnt just looting and pillaging with an army, its making an entire society dedicated to the war effort.
Sources Used:
Bicheno, Hugh. Total War. Edited by Richard Holmes et al., vol. 1, Oxford University Press, 2001
Segesser, Daniel Mark. Controversy: Total War. Vol. 1, International Encyclopedia of the First World War, 2017, encyclopedia.1914-1918-online.net/pdf/1914-1918-Online-controversy_total_war-2014-10-08.pdf.