La historia muestra la majestad del rey.

The sentence breaks down like this:

• La historia = the subject
• muestra = the verb
• la majestad del rey = the direct object

So structurally, it is:

Subject + verb + object

Spanish often uses the same basic word order as English in sentences like this.

Because historia is a feminine noun, so it takes la.

A common point of confusion is that some singular feminine nouns use el instead of la when they begin with a stressed a or ha sound, such as el agua or el hambre. But historia does not start with that kind of stressed sound, so it stays la historia.

Also, the h in historia is silent.

It can mean either one, depending on context.

• historia = history
• historia = story

Spanish uses the same word for both ideas, so the surrounding context tells you which meaning is intended.

Muestra is the third-person singular present form of mostrar, meaning to show.

It is muestra because the subject is la historia, which is singular.

Conjugation:

• yo muestro = I show
• tú muestras = you show
• él/ella muestra = he/she shows

So La historia muestra... means The story/history shows...

Yes. Muestra can also be a noun meaning sample or specimen.

But in this sentence, it is clearly a verb, because it comes after the subject la historia and functions as the action of the sentence.

So here:

• muestra = shows

Not:

• muestra = sample

Yes, majestad is a feminine noun, so it takes la.

A useful pattern is that many Spanish nouns ending in -dad are feminine:

• la ciudad
• la verdad
• la libertad
• la majestad

So la majestad is exactly what you would expect grammatically.

Del is the contraction of de + el.

So:

• de el rey becomes del rey

This contraction is required in normal Spanish.

Here, del rey means of the king.

A very important exception: if El is part of a proper name, the contraction is not used. For example:

• de El Escorial, not del Escorial

But with ordinary nouns like rey, you must use del.

Spanish often expresses possession with de, just like English can use of.

So:

• la majestad del rey = the majesty of the king

You could use a possessive in some contexts, but it would change the structure and sometimes the emphasis. In this sentence, del rey clearly identifies whose majesty is being shown.

It is a very normal and natural construction.

Spanish uses definite articles more often than English does.

In this sentence, you get:

• la historia
• la majestad
• del rey = de + el rey

Spanish is comfortable using articles with:

• general nouns
• abstract nouns
• possessed nouns

So even if English might sound lighter with articles in some situations, Spanish often keeps them. That is normal, not overly formal.

Because mostrar is usually the better choice for show in the sense of reveal, display, or present.

• mostrar = to show, reveal, display
• enseñar = to teach, or to show someone something physically

In this sentence, la historia muestra la majestad del rey means that the story/history reveals or presents the king’s majesty. That fits mostrar much better.

A simple pronunciation guide would be:

la is-TO-ria MWES-tra la ma-heh-STAHD del rey

A few important points:

• h in historia is silent
• muestra begins with mwe-
• j in majestad is a strong Spanish sound, like a rough h
• rey is one syllable, not two

So the rhythm is roughly:

La his-TO-ria MUES-tra la ma-jes-TAD del REY