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Good Luck Flag

Good Luck Flag is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Good Luck Flag rather than just read about it. In short: The Good Luck Flag (寄せ書き日の丸, yosegaki hinomaru) was a traditional gift for Japanese servicemen deployed during the military campaigns of the Empire of Japan, most notably during World War II. The flag was typically a national flag signed by friends and family, often with short messages wishing the soldier victory, safety and good luck.

Good Luck Flag — main illustration
Good Luck Flag — illustration

Key takeaways

  • Good Luck Flag belongs to science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Good Luck Flag to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Good Luck Flag from memory before moving on to harder problems.

Reference excerpt

The Good Luck Flag (寄せ書き日の丸, yosegaki hinomaru) was a traditional gift for Japanese servicemen deployed during the military campaigns of the Empire of Japan, most notably during World War II. The flag was typically a national flag signed by friends and family, often with short messages wishing the soldier victory, safety and good luck. Today, hinomaru are used for occasions such as charity and sporting events. The name 'hinomaru' is taken from the name for the flag of Japan, also known as hinomaru, which translates literally as "circular sun". When yosegaki hinomaru were signed by friends and relatives, the text written on the flag was generally written in a vertical formation radiating out from the central red circle, resembling the sun's rays. This appearance is referenced in the term 'yosegaki' (lit., "collection of writing"), meaning that the term 'yosegaki hinomaru' can be interpreted as a "collection of writing around the red sun", describing the appearance of text radiating outwards from the circle in the centre of the flag.

History The hinomaru yosegaki was traditionally presented to a man prior to his induction into the Japanese armed forces or before his deployment. The relatives, neighbors, friends, and co-workers of the person receiving the flag would write their names, good luck messages, exhortations, or other personal messages onto the flag in a formation resembling rays dissipating from the sun, though text was also written on any available space if the flag became crowded with messages. On some occasions, small caricatures or cartoons were added to the flag. In rare instances, elaborate and impressive art might also be placed on the flag. Sometimes good luck flags were decorated with images of black and white or colorful tigers. Hinomaru normally featured some kind of exhortation written across the top of the white field, such as bu-un chō-kyu (武運長久, "May your military fortunes be long lasting"); other typical decoration includes medium-sized characters along the right or left vertical margin of the flag, typically the name of the man receiving the flag, and the name of the individual or organization presenting it to him. The text written on the flag was commonly applied with a calligraphy brush and ink. While it was normally the custom to sign only around the red center of the flag, some examples may be found with characters written upon the red center as well. The origin of the custom of writing on flags is unclear, with some debate as to the time period when the custom first began. Some sources indicate that signed flags became part of a soldier's possessions, alongside a "thousand stitch belt" (senninbari), during the First Sino-Japanese War (1894–1895), though good luck flags predating the Manchurian Incident (1931) are considered rare. It is generally agreed that most hinomaru yosegaki seen today come from just before or during the period of the Second Sino-Japanese War (1937–1945). For the military man stationed far away from home and loved ones, the hinomaru yosegaki offered communal hopes and prayers to the owner every time the flag was unfolded. It was believed that the flag, with its many signatures and slogans, would provide a combined force or power to see its owner through tough times, as well as reminding the soldier of his duties in the war, with the implication that the performance of that duty meant that the warrior was not expected to return home from battle. Often, departing servicemen would leave behind clipped fingernails and hair, so that his relatives would have something of him in which to hold a funeral. The belief of self-sacrifice was central to Japanese culture during World War II, forming much of wartime sentiment. It was culturally believed that great honour was brought upon the family of those whose sons, husbands, brothers and fathers died in service to the country and the Emperor, and that in doing one's duty, any soldier, sailor or aviator would offer up his life freely. As part of the cultural samurai or bushido (way of the warrior) code, this worldview was brought forward into twentieth century Japan from the previous centuries of feudal Japan, and was impressed upon twentieth century soldiers, most of whom descended from non-samurai families.

U.S. veterans' accounts

In Sid Phillips's book, You'll Be Sor-ree, Phillips describes the role of Japanese flags in the Pacific War: "Every Jap seemed to have a personal silk flag with Jap writing all over it and a large meatball in the center." There are numerous books describing hinomaru as souvenirs taken home by U.S. Marines and members of the U.S. Army Infantry. Another example is found in Eugene Sledge's book, With the Old Breed: "The men gloated over, compared, and often swapped their prizes. It was a brutal, ghastly ritual the likes of which have occurred since ancient times on battlefields where antagonists have possessed a profound mutual hatred." In a 2008 article in the Monroe News, a World War II veteran spoke of his experiences bringing back a flag from the Pacific War, stating that he did not search every Japanese soldier he shot, as there was usually not enough time; the flag he eventually brought home was found on the island of Mindanao in the Philippines. According to his experiences, soldiers did not take home large souvenirs, such as katanas, for fear that someone would steal it, but a flag could be easily concealed. The flag he himself took as a souvenir was in the process of repatriation, with Dr. Yasuhiko Kaji searching for the owner and their family in Japan.

Effort to return flags The OBON SOCIETY (formerly OBON 2015) is a non-profit affiliate organization with a mission to return hinomaru to their families in Japan. The society's work has been recognized by Japan's Minister for Foreign Affairs as an "important symbol of reconciliation, mutual understanding, and friendship between our two countries". As of 2022, the society has returned more than 400 flags, and has more than 400 other flags they are currently working on returning. On 15 August 2017, the society arranged for Marvin Strombo, a 93-year-old American WWII veteran, to travel back to Japan to return the flag he took to the family of the man who made it. The effort to return the flags is widely seen as a humanitarian act providing closure for family members.

Preservation and restoration

… excerpt ends here. Continue reading the full article.

Illustrations

Good Luck Flag: Signed hinomaru belonging to Japanese soldier Eihachi Yamaguchi
Signed hinomaru belonging to Japanese soldier Eihachi Yamaguchi
Good Luck Flag illustration
Good Luck Flag illustration
Good Luck Flag illustration
Good Luck Flag illustration

Worked examples

Example 1 — a first encounter with Good Luck Flag

Start with the simplest possible case. Write down what Good Luck Flag claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Good Luck Flag before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Good Luck Flag ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Good Luck Flag

In research
Good Luck Flag appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Good Luck Flag in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Good Luck Flag is common in secondary-school and first-year university syllabi. It links to neighbouring topics Culture of Japan, Empire of Japan, Flags of Japan, so understanding it makes those chapters shorter.
In everyday life
Look for Good Luck Flag outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Good Luck Flag in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Good Luck Flag means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Good Luck Flag out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Good Luck Flag in simple terms?

The Good Luck Flag (寄せ書き日の丸, yosegaki hinomaru) was a traditional gift for Japanese servicemen deployed during the military campaigns of the Empire of Japan, most notably during World War II. The flag was typically a national flag signed by friends and family, often with short messages wishing the…

Why does Good Luck Flag matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Good Luck Flag?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Good Luck Flag.

Tags

  • Culture of Japan
  • Empire of Japan
  • Flags of Japan
  • Japanese inventions
  • Vexillology

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