Король подписал документ.

Подписал is the past tense, masculine singular form of the verb подписать.

• подписать = the infinitive
• подписал = signed / has signed (with a masculine subject)

In Russian, past tense forms are built differently depending on gender and number:

• masculine: подписал
• feminine: подписала
• neuter: подписало
• plural: подписали

Because король is masculine, the verb is подписал.

In Russian, past tense verbs agree with the subject in gender and number.

So:

• король is a masculine noun
• therefore the verb must be masculine too: подписал

Compare:

• Король подписал документ.
• Королева подписала документ.
• Окно закрылось. (neuter subject)
• Люди подписали документ. (plural subject)

This is different from English, where signed stays the same.

It is in the accusative, but for many inanimate masculine nouns, the accusative singular looks exactly like the nominative singular.

So:

• nominative: документ
• accusative: документ

That is why the direct object still appears as документ.

Compare with an animate masculine noun:

• nominative: король
• accusative: короля

So if the object were animate, the form would often change more visibly.

You know from a combination of:

• word order
• meaning
• verb behavior
• and sometimes context

In Король подписал документ, the normal Russian word order strongly suggests:

• Король = subject
• документ = direct object

Even though документ has the same form in nominative and accusative, the sentence structure makes the roles clear.

Russian has no articles.

So Король подписал документ could mean:

• The king signed the document
• A king signed a document
• The king signed a document

Which one sounds best depends on the context.

Russian usually leaves this information to:

• context
• word order
• intonation
• previous mention in the conversation

Подписал comes from the perfective verb подписать.

Perfective usually means the action is viewed as:

• completed
• whole
• result achieved

So Король подписал документ presents the signing as a completed event.

The imperfective partner is подписывать. Its past tense would be подписывал.

Very roughly:

• подписал = signed, completed the act
• подписывал = was signing / used to sign / signed repeatedly / was in the process of signing, depending on context

This is a very common question because it is about aspect, which is central in Russian.

• подписал = perfective
  Focuses on the completed result.
• подписывал = imperfective
  Focuses on the process, repetition, or the fact of the action without presenting it as a completed whole.

Examples:

• Король подписал документ.
  The king signed the document. The result is important: the document is now signed.

• Король подписывал документ.
  This could suggest:

  • he was in the middle of signing it,
  • he used to sign such documents,
  • or the action is being mentioned without stressing completion.

Yes. Russian does not have a separate tense built exactly like the English present perfect.

So подписал can often correspond to:

• signed
• has signed

The exact English translation depends on context.

For example:

• if you are narrating history, signed may sound best
• if you are announcing a result relevant now, has signed may sound better

Russian uses aspect and context where English often uses tense choice.

Yes. Russian word order is more flexible than English because case endings help show grammatical roles.

The neutral order here is:

• Король подписал документ.

But other orders are possible, for example:

• Документ подписал король.
• Подписал король документ.

These alternatives usually change the focus, emphasis, or style, not the core meaning.

For a beginner, it is best to treat Король подписал документ as the normal, neutral version.

The stress is:

• коро́ль
• подписа́л
• докуме́нт

A simple pronunciation guide:

• коро́ль ≈ ka-ROL'
• подписа́л ≈ pat-pee-SAL
• докуме́нт ≈ da-koo-MYENT

A few useful notes:

• Unstressed о is often pronounced more like a
• The final ль in король is soft
• Stress in Russian is very important and can move unpredictably, so it should be learned with each word

Here it is capitalized because it is the first word of the sentence.

If it appeared in the middle of a sentence as a common noun, it would normally be lowercase:

• Я видел короля.

Russian capitalizes:

• the first word of a sentence
• proper names
• some official titles in special contexts

But ordinary nouns like король are not normally capitalized just because they mean king.

The dictionary forms are:

• король — noun, masculine, king
• подписать — verb, perfective, to sign
• документ — noun, masculine, document

The sentence uses:

• король in the nominative singular
• подписал as the past masculine singular form of подписать
• документ in the accusative singular, which happens to look the same as the nominative

Yes, but that changes the tense and aspect.

• Король подписал документ.
  Past, completed action.

• Король подписывает документ.
  Present tense, imperfective: The king is signing the document / The king signs the document, depending on context.

So подписывает describes the action as ongoing or habitual, while подписал presents it as completed in the past.