diff --git a/client/src/services/__tests__/scryfall.test.ts b/client/src/services/__tests__/scryfall.test.ts
index 58f460ebbc..46b4a28841 100644
--- a/client/src/services/__tests__/scryfall.test.ts
+++ b/client/src/services/__tests__/scryfall.test.ts
@@ -11,12 +11,14 @@ const REPO_ROOT = path.resolve(
 );
 
 function makeLocalDataMap(
-  cards: Record<string, { name: string; mana_cost?: string; cmc?: number; type_line?: string }>,
+  cards: Record<string, { name: string; mana_cost?: string; cmc?: number; type_line?: string; oracle_id?: string }>,
 ): Response {
   const map: Record<string, unknown> = {};
   for (const [key, card] of Object.entries(cards)) {
     map[key.toLowerCase()] = {
       name: card.name,
+      oracle_id: card.oracle_id ?? key,
+      face_names: [card.name.toLowerCase()],
       mana_cost: card.mana_cost ?? "{1}",
       cmc: card.cmc ?? 1,
       type_line: card.type_line ?? "Instant",
@@ -157,6 +159,19 @@ describe("fetchCardData", () => {
 
     expect(card.name).toBe("Abrade");
   });
+
+  it("resolves ASCII names to diacritic local data keys (issue #1497)", async () => {
+    global.fetch = vi.fn().mockResolvedValueOnce(
+      makeLocalDataMap({
+        "éomer of the riddermark": { name: "Éomer of the Riddermark", oracle_id: "eomer-oracle" },
+      }),
+    );
+
+    const { resolveOracleIdSync, fetchCardImageUrl, loadScryfallData } = await loadScryfallModule();
+    await loadScryfallData();
+    expect(resolveOracleIdSync("Eomer of the Riddermark")).toBe("eomer-oracle");
+    await expect(fetchCardImageUrl("Eomer of the Riddermark", 0)).resolves.toMatch(/^https?:\/\//);
+  });
 });
 
 describe("fetchCardImageUrl", () => {
diff --git a/client/src/services/scryfall.ts b/client/src/services/scryfall.ts
index 2b1f5bc12a..e7ec11a919 100644
--- a/client/src/services/scryfall.ts
+++ b/client/src/services/scryfall.ts
@@ -50,6 +50,8 @@ type TokenImagesDataMap = Record<string, ScryfallDataEntry & { scryfall_id: stri
 
 let scryfallDataPromise: Promise<ScryfallDataMap | null> | null = null;
 let scryfallDataResolved: ScryfallDataMap | null = null;
+/** Maps diacritic-folded lowercase names to canonical scryfall-data keys. */
+let scryfallFoldedNameIndex: Map<string, string> | null = null;
 let printingsDataPromise: Promise<PrintingsDataMap | null> | null = null;
 let tokenImagesDataPromise: Promise<TokenImagesDataMap | null> | null = null;
 let scryfallQueue: Promise<void> = Promise.resolve();
@@ -60,6 +62,7 @@ export function loadScryfallData(): Promise<ScryfallDataMap | null> {
       .then((r) => r.json() as Promise<ScryfallDataMap>)
       .then((data) => {
         scryfallDataResolved = data;
+        scryfallFoldedNameIndex = buildFoldedNameIndex(data);
         return data;
       })
       .catch(() => null);
@@ -106,8 +109,8 @@ export async function getCardPrintings(oracleId: string): Promise<PrintingEntry[
 }
 
 export async function getCardPrintingsByName(cardName: string): Promise<PrintingEntry[]> {
-  const data = await loadScryfallData();
-  const entry = data?.[cardName.toLowerCase()];
+  await loadScryfallData();
+  const entry = lookupEntryByName(cardName);
   if (!entry) return [];
   return getCardPrintings(entry.oracle_id);
 }
@@ -130,7 +133,7 @@ export function findPrintingById(
 
 export function resolveOracleIdSync(cardName: string): string | null {
   if (!scryfallDataResolved) return null;
-  return scryfallDataResolved[cardName.toLowerCase()]?.oracle_id ?? null;
+  return lookupEntryByName(cardName)?.oracle_id ?? null;
 }
 
 /**
@@ -159,7 +162,7 @@ export function resolveFaceIndexSync(
 export function isCardImageRotatedSync(oracleId: string, cardName: string): boolean {
   if (!scryfallDataResolved) return false;
   const entry = scryfallDataResolved[oracleId.toLowerCase()]
-    ?? scryfallDataResolved[normalizeCardName(cardName).toLowerCase()];
+    ?? lookupEntryByName(cardName);
   return isSidewaysLayout(entry?.layout);
 }
 
@@ -169,7 +172,7 @@ export function isCardImageRotatedSync(oracleId: string, cardName: string): bool
 export function isCardImageFlipLayoutSync(oracleId: string, cardName: string): boolean {
   if (!scryfallDataResolved) return false;
   const entry = scryfallDataResolved[oracleId.toLowerCase()]
-    ?? scryfallDataResolved[normalizeCardName(cardName).toLowerCase()];
+    ?? lookupEntryByName(cardName);
   return isFlipLayout(entry?.layout);
 }
 
@@ -340,12 +343,40 @@ export function normalizeCardName(name: string): string {
     .trim();
 }
 
+/** Strip combining marks so "Eomer" matches "Éomer" in local image data. */
+function foldDiacritics(value: string): string {
+  return value.normalize("NFD").replace(/\p{M}/gu, "");
+}
+
+function buildFoldedNameIndex(data: ScryfallDataMap): Map<string, string> {
+  const index = new Map<string, string>();
+  for (const key of Object.keys(data)) {
+    const folded = foldDiacritics(key);
+    if (!index.has(folded)) {
+      index.set(folded, key);
+    }
+  }
+  return index;
+}
+
+function resolveNameLookupKey(name: string): string {
+  const normalized = normalizeCardName(name).toLowerCase();
+  if (!scryfallDataResolved) return normalized;
+  if (scryfallDataResolved[normalized]) return normalized;
+  const folded = foldDiacritics(normalized);
+  return scryfallFoldedNameIndex?.get(folded) ?? normalized;
+}
+
+function lookupEntryByName(name: string): ScryfallDataEntry | undefined {
+  if (!scryfallDataResolved) return undefined;
+  return scryfallDataResolved[resolveNameLookupKey(name)];
+}
+
 export async function fetchCardData(cardName: string): Promise<ScryfallCard> {
-  const name = normalizeCardName(cardName);
-  const localMap = await loadScryfallData();
-  const entry = localMap?.[name.toLowerCase()];
+  await loadScryfallData();
+  const entry = lookupEntryByName(cardName);
   if (!entry) {
-    throw new Error(`Card not in local data: "${name}"`);
+    throw new Error(`Card not in local data: "${normalizeCardName(cardName)}"`);
   }
   return {
     name: entry.name,
@@ -426,12 +457,12 @@ export async function fetchCardImageAsset(
   faceIndex: number,
   size: ImageSize = "normal",
 ): Promise<CardImageAsset> {
-  const data = await loadScryfallData();
-  const name = normalizeCardName(cardName).toLowerCase();
-  const entry = data?.[name];
+  await loadScryfallData();
+  const entry = lookupEntryByName(cardName);
   if (!entry) {
-    throw new Error(`Card image not in local data: "${name}"`);
+    throw new Error(`Card image not in local data: "${normalizeCardName(cardName)}"`);
   }
+  const name = resolveNameLookupKey(cardName);
   return resolveImageAsset(entry, faceIndex, size, name);
 }