"Thirty Years' War" meaning in English

{
  "head_templates": [
    {
      "args": {
        "head": "Thirty Years' War"
      },
      "expansion": "Thirty Years' War",
      "name": "en-proper noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Historical events",
          "orig": "en:Historical events",
          "parents": [
            "History",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A conflict fought largely within the Holy Roman Empire from 1618 to 1648."
      ],
      "id": "en-Thirty_Years'_War-en-name-FQORcxCG",
      "links": [
        [
          "Holy Roman Empire",
          "Holy Roman Empire"
        ]
      ],
      "raw_glosses": [
        "(historical) A conflict fought largely within the Holy Roman Empire from 1618 to 1648."
      ],
      "related": [
        {
          "word": "Eighty Years' War"
        }
      ],
      "tags": [
        "historical"
      ],
      "wikipedia": [
        "Thirty Years' War"
      ]
    }
  ],
  "word": "Thirty Years' War"
}

{
  "head_templates": [
    {
      "args": {
        "head": "Thirty Years' War"
      },
      "expansion": "Thirty Years' War",
      "name": "en-proper noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "related": [
    {
      "word": "Eighty Years' War"
    }
  ],
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English proper nouns",
        "English terms with historical senses",
        "English terms with non-redundant non-automated sortkeys",
        "English uncountable nouns",
        "en:Historical events"
      ],
      "glosses": [
        "A conflict fought largely within the Holy Roman Empire from 1618 to 1648."
      ],
      "links": [
        [
          "Holy Roman Empire",
          "Holy Roman Empire"
        ]
      ],
      "raw_glosses": [
        "(historical) A conflict fought largely within the Holy Roman Empire from 1618 to 1648."
      ],
      "tags": [
        "historical"
      ],
      "wikipedia": [
        "Thirty Years' War"
      ]
    }
  ],
  "word": "Thirty Years' War"
}