engineering

Shigisan Castle

Shigisan Castle is a engineering 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 Shigisan Castle rather than just read about it. In short: Shigisan castle (信貴山城, Shigisanjō) was a Japanese castle of the Sengoku period, controlled by the Kizawa and Matsunaga clans. There are little remains of the castle on the present day site, just some moats and earthworks.

Key takeaways

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

Reference excerpt

Shigisan castle (信貴山城, Shigisanjō) was a Japanese castle of the Sengoku period, controlled by the Kizawa and Matsunaga clans. There are little remains of the castle on the present day site, just some moats and earthworks.

Location The castle was located atop Mount Shigi, on the border of Japan's Kawachi and Yamato Provinces (today Nara prefecture). The shugo (shogunal governors) and later daimyō of Yamato province ruled the province from Shigisan, and wielded some control over the strategic passes between Yamato and Kawachi. The location was also significant for the temple of Chōgosonshi-ji, which sits on the mountainside, some distance below the castle. Shigisan is the central mountain of the Shingon sect of Buddhism, and is claimed to be the location where, in 587, Shōtoku Taishi defeated Mononobe no Moriya in the battle of Shigisan.

History The castle was originally constructed in 1536 by Kizawa Nagamasa, who commanded it on behalf of the Hatakeyama clan, who held the post of shugo of Yamato province. It was repaired and expanded on in 1559, by Matsunaga Danjo Hisahide, who commanded it on behalf of the Miyoshi clan. It would grow to be roughly 700m from north to south, and 550m from east to west, and included a four-story yagura (tower or turret). In 1562, however, the daimyo of Yamato province moved to Tamonyama Castle. Shigisan castle fell to members of the Miyoshi clan in 1568, but was recaptured quickly afterwards when the attackers' attention was redirected to the capital by the activities of Oda Nobunaga. Nobunaga would then besiege the castle in 1577, destroying it and bringing the downfall of Matsunaga Hisahide.

See also Shigisan-engi List of Historic Sites of Japan (Nara)

References

The information in this article is based largely upon that in the corresponding article on the Japanese Wikipedia, accessed 8 January 2008.

Illustrations

Worked examples

Example 1 — a first encounter with Shigisan Castle

Start with the simplest possible case. Write down what Shigisan Castle claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, 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 Shigisan Castle 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 Shigisan Castle 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 Shigisan Castle

In research: Shigisan Castle appears in engineering 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 Shigisan Castle 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: Shigisan Castle is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1530s establishments in Japan, 1536 establishments in Japan, Buildings and structures completed in 1536, so understanding it makes those chapters shorter.
In everyday life: Look for Shigisan Castle 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.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Shigisan Castle” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Shigisan Castle in 20 minutes

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

Frequently asked questions

What is Shigisan Castle in simple terms?

Why does Shigisan Castle matter?

Because it connects several engineering 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 Shigisan Castle?

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 Shigisan Castle.