Help making a Death Knight style character

[Corsair14]

How would I go about making a Death Knight, kind of like Lord Soth but alive? Been bouncing this idea around all morning at work.
Looking at carrying a bastard or great sword.
Ability to wear heavy armor
Evocation(fire) and Necromancy spells
Human or variant human
Not necessarily evil, looking at Lawful Neutral but lawful evil is ok at this stage.
Probably will be a Strength, Int, Con character
Probably no more than 2 classes in a multiclass. Most campaigns rarely go through more then ten levels so I am aware I will never hit legendary status so I need abilities as front loaded as possible thus splitting my levels as little as possible is preferable. Mostly an offensive character who deals with undead. I know summoning is absurdly nerfed in 5e so I am happy to be more capable of dealing with the undead than I am summoning them.

Also using book rules, no homebrew.

[Paeleus]

Oathbreaker Paladin is exactly what you want. DM's blessing required, tho.

[Corsair14]

Assuming with a multi-class with a necromancer?

[Teaguethebean]

Assuming with a multi-class with a necromancer?

Not really necessary as you can raise dead and control them with an oatbreaker. I was planning on making a death knight homebrew for my ebberon game but I realized resigning oathbreaker did the job to a tea.

[AgenderArcee]

Oathbreaker gives you everything you want except the fire spells (other than Hellish Rebuke, which is only a reaction), but it is worth noting that you won't get Animate Dead until level 9 since it's a half-caster. A potential alternative if you want undead minions earlier could be starting Fighter 1 for heavy armor/martial weapons and then taking six levels of Necromancer Wizard, which will give you more and stronger Undead Thralls than you would have with any other class, as well as all the fire/evocation spells you could want. You could then switch back to Fighter and become an Eldritch Knight up to at least level 7, or any other Fighter class.

You could do Wizard/Paladin and have both the Necromancer and Oathbreaker subclasses, but it'd be quite MAD considering that you would want high Strength, Charisma and Intelligence.

Also worth noting that your HP would take a hit if you take Wizard levels.

Another alternative that would delay Animate Dead slightly more but get you fire spells and be less MAD would be to make an Oathbreaker Sorcadin (Divine Soul maybe) or Padlock (Fiend). If you're playing with UA Class Feature Variants, the Warlock route might be best because Animate Dead was added to their spell list, so you could get it at Warlock 5 instead of Paladin 9. You could even go straight Fiendlock and take Pact of the Blade for Extra Attack, Eldritch Armor and other evocations. Note that you would be restricted to light armor until Level 3, though, without multiclassing.

[GlenSmash!]

Oathbreaker with Fiend Pact Warlock will get you some fire spells.

[Trask]

I think a Oath of Conquest/Fiendlock MC would be fine if your DM doesnt like Oathbreaker.

[Arkhios]

I'd lean towards Eldritch Knight myself.

If your DM is fair and lenient, you could ask if you can alter Eldritch Knight's default schools from Abjuration and Evocation to Evocation and Necromancy. It shouldn't break anything, as long as you follow other rules as normal.

Even if this is out of question, Abjuration, Evocation, and the occasional Necromancy spells are all good for you.

[Nagog]

When you say "Book Rules, No Homebrew", does that also disallow UA? If not, the Class Varients UA gives you everything you need. Warlocks get Animate Dead (and on a short rest, that works wonders), and the Eldritch Armor grants you Heavy Armor Prof (and the ability to don it instantly). My Wizard Necromancer also has Dancing Lights, which can be cast in the shape of a humanoid to look like a ghost or spirit under your command for early flavor. Pact of the Blade and Eldritch Armor can turn any subclass into a martial class, so you could go Fiend for the fire spells, or Hexblade for more of a martial focus.

All in all, since the UA gave Warlocks Animate Dead on a short rest, they have the best potential for a Death Knight/Necromancer.

[Corsair14]

Ill have to go look into that. Not sure if UA is an option. I was mainly talking about homebrew stuff in my comment, there's obviously homebrew for anything.