If you're looking for manga similar to Ecchan no Sensou, you might like these titles.
Set in the aftermath of World War II, this is the story of Kazuko, a strong-willed young woman from an aristocratic family that has fallen into poverty since the war. The book follows Kazuko's journey as she and her family struggle to survive and adapt to the harsh new conditions. In addition to having to move from Tokyo to the countryside, where she is forced to work in the fields to support the family, she has to deal with a difficult divorce, the birth of a stillborn child, and the return of her drug-addicted brother from the war. This gripping and inspiring portrait of one woman's determination to survive in a society that is in the grip of a social and moral crisis tells one story in a fast-changing world, with universal themes that resonates with readers today.
In the final days of World War II, Japan lay in ruins and the cities of Hiroshima and Nagasaki had been obliterated. A tense drama unfolds in Tokyo as Japan teeters on the edge of Armageddon. Japan's Longest Day tells the true story of the day immediately before the surrender, as a group of fanatical army officers attempt to prevent the Emperor from surrendering—an act of high treason which will inevitably result in Japan's total annihilation.
In 1905, Vergille Strauss is a young thief living in the small country of Apfelland. With the help of a local inspector named Fleischer, he rescues a girl from a group of foreign thugs. Her name is Frieda and she may be the key to a secret that is of great interest to other nations.