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Two new monoclinic (<i>P</i>2₁/<i>m</i>) epidote supergroup minerals manganiakasakaite-(La) and ferriakasakaite-(Ce) were found in the small Mn ore deposit of Monte Maniglia, Bellino, Varaita Valley, Cuneo Province, Piedmont, Italy. Manganiakasakaite-(La) occurs as subhedral grains embedded in pyroxmangite. Its empirical formula is <i>^A</i>⁽¹⁾(Ca_0.62Mn²⁺_0.38) <i>^A</i>⁽²⁾(La_0.52Nd_0.08Pr_0.07Ce_0.07Y_0.01Ca_0.25) <i>^M</i>⁽¹⁾(Mn³⁺_0.52Fe³⁺_0.28Al_0.18V³⁺_0.01) <i>^M</i>⁽²⁾Al_1.00 <i>^M</i>⁽³⁾(Mn²⁺_0.60Mn³⁺_0.27Mg_0.13) <i>^T</i>^(1&#8722;3)(Si_2.99Al_0.01) O₁₂ (OH), corresponding to the end-member formula CaLaMn³⁺AlMn²⁺(Si₂O₇)(SiO₄)O(OH). Unit-cell parameters are <i>a</i> = 8.9057(10), <i>b</i> = 5.7294(6), <i>c</i> = 10.1134(11) &#197;, &#946; = 113.713(5)&#176;, <i>V</i> = 472.46(9) &#197;³, <i>Z</i> = 2. The crystal structure of manganiakasakaite-(La) was refined to a final <i>R</i>₁ = 0.0262 for 2119 reflections with <i>F</i>_o &gt; 4&#963;(<i>F</i>_o) and 125 refined parameters. Ferriakasakaite-(Ce) occurs as small homogeneous domains within strongly inhomogeneous prismatic crystals, where other epidote supergroup minerals coexist [manganiandrosite-(Ce), &#8220;androsite-(Ce)&#8221;, and epidote]. Associated minerals are calcite and hematite. Its empirical formula is <i>^A</i>⁽¹⁾(Ca_0.64Mn²⁺_0.36) <i>^A</i>⁽²⁾(Ce_0.37La_0.17Nd_0.06Pr_0.03Ca_0.35□_0.02) <i>^M</i>⁽¹⁾(Fe³⁺_0.61Al_0.39) <i>^M</i>⁽²⁾Al_1.00 <i>^M</i>⁽³⁾(Mn²⁺_0.64Mn³⁺_0.33Fe³⁺_0.02Mg_0.01) <i>^T</i>^(1&#8722;3)Si_3.01 O₁₂ (OH), the end-member formula being CaCeFe³⁺AlMn²⁺(Si₂O₇)(SiO₄)O(OH). Unit-cell parameters are <i>a</i> = 8.9033(3), <i>b</i> = 5.7066(2), <i>c</i> = 10.1363(3) &#197;, &#946; = 114.222(2)&#176;, <i>V</i> = 469.66(3) &#197;³, <i>Z</i> = 2. The crystal structure of ferriakasakaite-(Ce) was refined to a final <i>R</i>₁ = 0.0196 for 1960 unique reflections with <i>F</i>_o &gt; 4&#963;(<i>F</i>_o) and 124 refined parameters.