I have seen timelines used in lots of subjects, not just History, to great effect. They are effective ways to help learners grasp when events happen and how concepts and ideas have developed over time.
In @BBGHistory‘s example, the shape of timeline represents a road showing the route out of the war, but initially I thought these where drawn as tunnels like the ones in Củ Chi used by the Vietcong. Perhaps this might be an idea for future lesson. In @becbouche‘s example at the bottom of this post, the timeline is annotated with coloured clouds in which the student has added information. I really like to key on the side which delineates between types of information e.g. “propaganda” or “Hitler and his image”. It looks like the teacher has also added a square orange block for the student to expand on part of the timeline as part of the feedback.