The stamps from the Kingdom of Bavaria, or Bayern, issued in 1914–1915, are highly prized by collectors for their historical significance and rarity. This period is particularly notable due to the outbreak of World War I, marking the end of Bavaria as an independent kingdom within the German Empire. The reigning monarch during this time was King Ludwig III, who assumed the throne in 1913. Ludwig III's reign symbolized the last chapter of Bavarian independence, as Bavaria would soon be absorbed into the German Empire in 1918 following the end of the war.

The high-denomination Bavarian stamps, especially the 5 Mark blue, 10 Mark green, and 20 Mark brown, are particularly coveted among philatelists. These stamps, which featured intricate designs and vivid colors, were intended for high-value shipments and thus were produced in limited quantities. The cancellation, or postmark, on these stamps often adds to their value, as a clearly visible cancellation is a mark of authenticity and enhances their historical appeal. These postmarks reveal where and when the stamps were used, often in significant cities like Munich or Nuremberg, linking them directly to Bavaria’s rich postal history.

The **5 Mark blue stamp** stands out due to its bold color and design, which included Bavarian emblems and stylized patterns that evoke the traditional Bavarian style. This stamp was issued primarily for international and valuable parcel shipments, meaning only a limited number reached circulation. It’s an exceptional find for collectors, especially if it carries a crisp and identifiable cancellation.

Similarly, the **10 Mark green stamp** is another prized piece, often linked to higher postal tariffs associated with overseas trade. This stamp’s vibrant green color and detailed artwork represented Bavaria’s pride and autonomy within the German Empire, symbolizing its significant cultural and economic role.

Finally, the **20 Mark brown stamp** is the rarest and most valuable among this series. Used almost exclusively for special packages and urgent deliveries, these stamps were rarely seen by the public and even more rarely preserved. This makes them a gem in any collection, particularly when stamped with a Bavarian postmark from 1914 or 1915.

Together, these high-denomination stamps offer a unique glimpse into Bavaria's final years as a kingdom, symbolizing its rich heritage and the personal touch of King Ludwig III's reign. Collectors consider these stamps not only for their artistic and historic worth but also as rare artifacts from the twilight of Bavarian monarchy, capturing a moment of profound historical transition.