You could check out 'Vinland Saga'. It has elements of historical fiction, warfare, and character-driven plots similar to Kingdom. But it has a distinct Nordic setting.
I'd suggest 'Berserk'. It has a similar dark and gritty tone, along with intense action and deep storylines like Kingdom. However, the art style is quite different.
Chapter 309, "Then Come Die with Me!", is the clearest early answer because it turns Hua Country's situation into a concrete plot event.
Chapter 322, "Water Breaks Heaven's Heart", is the clearest early answer because it turns Water Breaks Heaven's situation into a concrete plot event.
Chapter 634, "All Villains", is the clearest early answer because it turns Lin Muyang's situation into a concrete plot event.
Chapter 395, "She's Not Trying to Use Under-the-Table Tactics, Is She?", is the clearest early answer because it turns Qin Feng's situation into a concrete plot event. Early on, He had thought that Jiang Li wanted the lead role to control the....
Chapter 472, "The Stream Dried Up?!", is the clearest early answer because it turns Shang Shaojing's situation into a concrete plot event.
Chapter 533, "Sister Li, When Did You Become a Clamp?!", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. The chapter turns that into something concrete by moving from The sycophant had gone crazy too.
Chapter 540, "I am the Young Master's Nanny", is the clearest early answer because it turns Lu Long's situation into a concrete plot event. The chapter gives readers a real answer by opening on Compared to Lu Long's impulsiveness, Lu Hu seemed much more composed.
Chapter 561, "How Can This Young Master Use His Hands to Kill Fish?", is the clearest early answer because the violence around Jiang Li becomes final instead of hypothetical.
Chapter 436, "Do You Remember Brother Daniu by Daming Lake?", is the clearest early answer because it turns Wilderness Survival's situation into a concrete plot event.
Chapter 817, "Killed by Me", is the clearest early answer because the violence around Jiang Yan becomes final instead of hypothetical. Early on, Jiang Buchen leaned against Meng Wanzhi's chest and thoughtfully.... By the end, Her brother had always been unwell since birth, so her parents....