The Greeks invented history as it would develop in Western thought, and different early historians approached the issue of history in different ways. The approach taken often depended on whether they were eyewitnesses or reporting what others told them, on their skill as writers, and on whether they offer judgments about the history they recount or only tell the stories as they know them. Thucydides wrote about the Peloponnesian War and its consequences in a way that would speak to future generations, and he did so from the point of view of an eyewitness and participant. Tacitus examined history in terms of individuals and groups, offering as much cultural as historical analysis, and reporting on people he knew, letting them tell their own stories through him.
The Peloponnesian War between Athens and Sparta was an event that had major consequences for the development of the ancient world, with the details of this war reported to the ages by the historian Thucydides. His approach to history would influence later writers and continue to stand as one of the most important histories of the Greek world. He helped develop the idea of what history means through the method he used, which included a philosophical element that tried to explain events and relate them to a larger consciousness of the world and of human aspirations.
Thucydides discusses his historical method and related issues in the early section, known as the "Archaeology" section. He shows a journalistic tendency in that he started to write about the war as soon as it started, claiming that he expected it would turn out to be a great war and so one that would deserve to be recorded (Thucydides writes of himself in the third person): "The preparations of both the combatants were in every department in the last state of perfection; and he could see the rest of the Hellenic race taking sides in the quarrel, those who delayed doing so at once having it in contemp...