理查一世（英語：Richard I；1157年9月8日—1199年4月6日）是中世紀英格蘭王國的國王，也是阿基坦、諾曼第、加斯科涅公爵，塞浦路斯國王和普瓦捷、南斯、曼恩、安茹伯爵，同時在一段時間內數次成為布列塔尼君主，因驍勇善戰而被譽為「獅心王」（法語：Cœur de Lion；英語：Richard the Lionheart）。理查一世作為虔誠的基督教教徒，畢生奉獻於教廷發起的第三次十字軍東征，並因於阿爾蘇夫戰役中擊潰薩拉丁麾下穆斯林大軍而一戰成名[1]。
本來阿卡的穆斯林駐軍被基督教世界軍隊包圍，薩拉丁率領的更強大穆斯林軍隊又包圍基督教世界軍隊，但理查到來後不久就攻取阿卡。攻取阿卡後，理查又與奧地利公爵利奧波德五世就戰利品瓜分發生爭吵，加上腓力回國，此時十字軍遠征遭受重創。這次十字軍的領導者腓力二世和理查之間芥蒂甚深。腓力處心積慮要奪回英格蘭在法蘭西王國的領地。理查年輕時與腓力之姐法蘭西的艾莉絲（英語：Alix of France）訂婚，但理查卻認為艾莉絲是其父的情婦而堅決不娶。
綿延不絕的軍事行動使理查常感匱乏，一項關於寶藏的謠言激起他貪欲。法國沙露堡（英語：Château de Châlus-Chabrol）的利摩日子爵拒絕交出一大筆由農民發現的巨額黃金，因此理查出兵包圍該城堡，更揚言要絞死城裹全部居民。在包圍的過程中，他一如既往身先士卒勇猛作戰，卻不慎被堡中發出的一支弩箭射中肩胛，本來想要拔除箭，不料箭頭斷入體內，10天後身亡，年42歲。臨終前，他要求將遺體分為三份，心臟、頭、身體分別埋葬，其中身體埋在其父亨利二世腳下，以示懺悔。
理查身後沒有婚生子嗣，只有一個被他認可的私生子干邑的腓力（英語：Philip of Cognac）。他的弟弟約翰繼承了英格蘭皇位[6]，但法國領主們喜歡按現行繼承法讓他有更優先繼承權的已故弟弟傑弗瑞的兒子阿蒂爾繼承，拒絕臣服約翰[7]。理查沒有直系繼承人成為安茹帝國解體的導火索[6]。此後的英格蘭國王們儘管主張這些法國領地，卻再也沒能恢復理查繼位時的疆界。
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